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string
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math-001201
Number Theory: Congruences — Efficient Exponentiation
1
Make each step logically reversible (or explain if not): Compute the remainder when $19^100$ is divided by $100$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency ch...
[ { "method_name": "Residue Cycle / Euler–Totient Heuristic", "approach": "Use that residues modulo $m$ often repeat with a period; for $m\\in\\{10,20,100\\}$, last-digit/two-digit cycles are short and can be tracked explicitly.", "steps": [ "Step 1: Consider the sequence $a^1\\bmod 100, a^2\\bmod 1...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{1}$.\nBoth methods compute the same residue class of $a^b$ modulo 100: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yie...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Remember: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small.
math-001202
Number Theory: Residues — Last Digits / Two Digits
1
Provide both a computational and a conceptual explanation: Compute the remainder when $51^38$ is divided by $100$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency c...
[ { "method_name": "Repeated Squaring", "approach": "Use exponentiation by squaring to compute $a^b\\bmod m$ efficiently, reducing modulo $m$ after each multiplication.", "steps": [ "Step 1: Work modulo 100 throughout; replace $a$ by $a\\bmod 100$ to start.", "Step 2: Compute successive square...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{1}$.\nBoth methods compute the same residue class of $a^b$ modulo 100: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yie...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Takeaway: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small. (Here the result is $\boxed{1}$.)
math-001203
Discrete Math: Modular Computation — Avoid Huge Integers
1
Carefully track domains: Compute the remainder when $3^54$ is divided by $20$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mod 5/mod 4 re...
[ { "method_name": "Repeated Squaring", "approach": "Use exponentiation by squaring to compute $a^b\\bmod m$ efficiently, reducing modulo $m$ after each multiplication.", "steps": [ "Step 1: Work modulo 20 throughout; replace $a$ by $a\\bmod 20$ to start.", "Step 2: Compute successive squares ...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{9}$.\nBoth methods compute the same residue class of $a^b$ modulo 20: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yield remainder 9.", "rob...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Remember: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small.
math-001204
Number Theory: Modular Arithmetic — Cycles and Periods
1
Warm-up: Compute the remainder when $12^79$ is divided by $20$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mod 5/mod 4 reasoning). Your...
[ { "method_name": "Repeated Squaring", "approach": "Use exponentiation by squaring to compute $a^b\\bmod m$ efficiently, reducing modulo $m$ after each multiplication.", "steps": [ "Step 1: Work modulo 20 throughout; replace $a$ by $a\\bmod 20$ to start.", "Step 2: Compute successive squares ...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{8}$.\nBoth methods compute the same residue class of $a^b$ modulo 20: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. ...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Core principle: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small.
math-001205
Number Theory: Modular Arithmetic — Cycles and Periods
1
Start by stating any domain restrictions: Compute the remainder when $8^171$ is divided by $20$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity...
[ { "method_name": "Residue Cycle / Euler–Totient Heuristic", "approach": "Use that residues modulo $m$ often repeat with a period; for $m\\in\\{10,20,100\\}$, last-digit/two-digit cycles are short and can be tracked explicitly.", "steps": [ "Step 1: Consider the sequence $a^1\\bmod 20, a^2\\bmod 20...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{12}$.\nBoth methods compute the same residue class of $a^b$ modulo 20: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yield remainder 12.", "r...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Takeaway: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small. (Here the result is $\boxed{12}$.)
math-001206
Discrete Math: Modular Computation — Avoid Huge Integers
1
Give a theorem-based solution: Compute the remainder when $88^165$ is divided by $100$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mod 5...
[ { "method_name": "Residue Cycle / Euler–Totient Heuristic", "approach": "Use that residues modulo $m$ often repeat with a period; for $m\\in\\{10,20,100\\}$, last-digit/two-digit cycles are short and can be tracked explicitly.", "steps": [ "Step 1: Consider the sequence $a^1\\bmod 100, a^2\\bmod 1...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{68}$.\nBoth methods compute the same residue class of $a^b$ modulo 100: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yield remainder 68.", "...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Core principle: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small. (Here the result is $\boxed{68}$.)
math-001207
Number Theory: Residues — Last Digits / Two Digits
1
Where appropriate, name the theorem you use: Compute the remainder when $98^155$ is divided by $100$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., p...
[ { "method_name": "Repeated Squaring", "approach": "Use exponentiation by squaring to compute $a^b\\bmod m$ efficiently, reducing modulo $m$ after each multiplication.", "steps": [ "Step 1: Work modulo 100 throughout; replace $a$ by $a\\bmod 100$ to start.", "Step 2: Compute successive square...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{32}$.\nBoth methods compute the same residue class of $a^b$ modulo 100: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Core principle: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small.
math-001208
Number Theory: Modular Arithmetic — Cycles and Periods
1
Problem: Compute the remainder when $95^145$ is divided by $100$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mod 5/mod 4 reasoning). Yo...
[ { "method_name": "Residue Cycle / Euler–Totient Heuristic", "approach": "Use that residues modulo $m$ often repeat with a period; for $m\\in\\{10,20,100\\}$, last-digit/two-digit cycles are short and can be tracked explicitly.", "steps": [ "Step 1: Consider the sequence $a^1\\bmod 100, a^2\\bmod 1...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{75}$.\nBoth methods compute the same residue class of $a^b$ modulo 100: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Takeaway: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small.
math-001209
Number Theory: Residues — Last Digits / Two Digits
1
Solve with verification: Compute the remainder when $14^160$ is divided by $10$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mod 5/mod 4 ...
[ { "method_name": "Residue Cycle / Euler–Totient Heuristic", "approach": "Use that residues modulo $m$ often repeat with a period; for $m\\in\\{10,20,100\\}$, last-digit/two-digit cycles are short and can be tracked explicitly.", "steps": [ "Step 1: Consider the sequence $a^1\\bmod 10, a^2\\bmod 10...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{6}$.\nBoth methods compute the same residue class of $a^b$ modulo 10: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yiel...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Takeaway: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small. (Here the result is $\boxed{6}$.)
math-001210
Number Theory: Congruences — Efficient Exponentiation
1
Problem: Compute the remainder when $29^182$ is divided by $20$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mod 5/mod 4 reasoning). You...
[ { "method_name": "Residue Cycle / Euler–Totient Heuristic", "approach": "Use that residues modulo $m$ often repeat with a period; for $m\\in\\{10,20,100\\}$, last-digit/two-digit cycles are short and can be tracked explicitly.", "steps": [ "Step 1: Consider the sequence $a^1\\bmod 20, a^2\\bmod 20...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{1}$.\nBoth methods compute the same residue class of $a^b$ modulo 20: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yield remainder 1.", "rob...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Core principle: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small.
math-001211
Number Theory: Residues — Last Digits / Two Digits
1
Task: Compute the remainder when $43^188$ is divided by $10$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mod 5/mod 4 reasoning). Your w...
[ { "method_name": "Residue Cycle / Euler–Totient Heuristic", "approach": "Use that residues modulo $m$ often repeat with a period; for $m\\in\\{10,20,100\\}$, last-digit/two-digit cycles are short and can be tracked explicitly.", "steps": [ "Step 1: Consider the sequence $a^1\\bmod 10, a^2\\bmod 10...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{1}$.\nBoth methods compute the same residue class of $a^b$ modulo 10: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yiel...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Core principle: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small.
math-001212
Number Theory: Residues — Last Digits / Two Digits
1
Answer with a short justification: Compute the remainder when $15^90$ is divided by $20$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mod...
[ { "method_name": "Repeated Squaring", "approach": "Use exponentiation by squaring to compute $a^b\\bmod m$ efficiently, reducing modulo $m$ after each multiplication.", "steps": [ "Step 1: Work modulo 20 throughout; replace $a$ by $a\\bmod 20$ to start.", "Step 2: Compute successive squares ...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{5}$.\nBoth methods compute the same residue class of $a^b$ modulo 20: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yiel...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Key idea: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small. (Here the result is $\boxed{5}$.)
math-001213
Discrete Math: Modular Computation — Avoid Huge Integers
1
Keep the final answer in boxed form: Compute the remainder when $28^203$ is divided by $100$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or...
[ { "method_name": "Residue Cycle / Euler–Totient Heuristic", "approach": "Use that residues modulo $m$ often repeat with a period; for $m\\in\\{10,20,100\\}$, last-digit/two-digit cycles are short and can be tracked explicitly.", "steps": [ "Step 1: Consider the sequence $a^1\\bmod 100, a^2\\bmod 1...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{52}$.\nBoth methods compute the same residue class of $a^b$ modulo 100: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yield remainder 52....
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Takeaway: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small.
math-001214
Number Theory: Congruences — Efficient Exponentiation
1
Find the exact value: Compute the remainder when $42^147$ is divided by $20$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mod 5/mod 4 rea...
[ { "method_name": "Repeated Squaring", "approach": "Use exponentiation by squaring to compute $a^b\\bmod m$ efficiently, reducing modulo $m$ after each multiplication.", "steps": [ "Step 1: Work modulo 20 throughout; replace $a$ by $a\\bmod 20$ to start.", "Step 2: Compute successive squares ...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{8}$.\nBoth methods compute the same residue class of $a^b$ modulo 20: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yield remainder 8.", ...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Key idea: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small. (Here the result is $\boxed{8}$.)
math-001215
Number Theory: Modular Arithmetic — Repeated Squaring
1
Give a fully justified solution: Compute the remainder when $54^152$ is divided by $10$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mod ...
[ { "method_name": "Repeated Squaring", "approach": "Use exponentiation by squaring to compute $a^b\\bmod m$ efficiently, reducing modulo $m$ after each multiplication.", "steps": [ "Step 1: Work modulo 10 throughout; replace $a$ by $a\\bmod 10$ to start.", "Step 2: Compute successive squares ...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{6}$.\nBoth methods compute the same residue class of $a^b$ modulo 10: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yield remainder 6.", "rob...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Takeaway: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small.
math-001216
Number Theory: Residues — Last Digits / Two Digits
1
Show all reasoning: Compute the remainder when $40^95$ is divided by $20$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mod 5/mod 4 reason...
[ { "method_name": "Residue Cycle / Euler–Totient Heuristic", "approach": "Use that residues modulo $m$ often repeat with a period; for $m\\in\\{10,20,100\\}$, last-digit/two-digit cycles are short and can be tracked explicitly.", "steps": [ "Step 1: Consider the sequence $a^1\\bmod 20, a^2\\bmod 20...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{0}$.\nBoth methods compute the same residue class of $a^b$ modulo 20: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yield remainder 0.", ...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Key idea: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small.
math-001217
Number Theory: Modular Arithmetic — Cycles and Periods
1
Keep the final answer in boxed form: Compute the remainder when $83^98$ is divided by $10$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or m...
[ { "method_name": "Repeated Squaring", "approach": "Use exponentiation by squaring to compute $a^b\\bmod m$ efficiently, reducing modulo $m$ after each multiplication.", "steps": [ "Step 1: Work modulo 10 throughout; replace $a$ by $a\\bmod 10$ to start.", "Step 2: Compute successive squares ...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{9}$.\nBoth methods compute the same residue class of $a^b$ modulo 10: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. ...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Core principle: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small. (Here the result is $\boxed{9}$.)
math-001218
Number Theory: Modular Arithmetic — Cycles and Periods
1
Track quantifiers carefully: Compute the remainder when $42^58$ is divided by $20$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mod 5/mod...
[ { "method_name": "Residue Cycle / Euler–Totient Heuristic", "approach": "Use that residues modulo $m$ often repeat with a period; for $m\\in\\{10,20,100\\}$, last-digit/two-digit cycles are short and can be tracked explicitly.", "steps": [ "Step 1: Consider the sequence $a^1\\bmod 20, a^2\\bmod 20...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{4}$.\nBoth methods compute the same residue class of $a^b$ modulo 20: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yiel...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Core principle: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small. (Here the result is $\boxed{4}$.)
math-001219
Number Theory: Residues — Last Digits / Two Digits
1
Answer using clear logical steps: Compute the remainder when $2^142$ is divided by $100$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mod...
[ { "method_name": "Residue Cycle / Euler–Totient Heuristic", "approach": "Use that residues modulo $m$ often repeat with a period; for $m\\in\\{10,20,100\\}$, last-digit/two-digit cycles are short and can be tracked explicitly.", "steps": [ "Step 1: Consider the sequence $a^1\\bmod 100, a^2\\bmod 1...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{4}$.\nBoth methods compute the same residue class of $a^b$ modulo 100: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yie...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Takeaway: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small.
math-001220
Number Theory: Congruences — Efficient Exponentiation
1
Exercise: Compute the remainder when $53^208$ is divided by $20$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mod 5/mod 4 reasoning). Yo...
[ { "method_name": "Residue Cycle / Euler–Totient Heuristic", "approach": "Use that residues modulo $m$ often repeat with a period; for $m\\in\\{10,20,100\\}$, last-digit/two-digit cycles are short and can be tracked explicitly.", "steps": [ "Step 1: Consider the sequence $a^1\\bmod 20, a^2\\bmod 20...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{1}$.\nBoth methods compute the same residue class of $a^b$ modulo 20: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yiel...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Takeaway: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small.
math-001221
Number Theory: Residues — Last Digits / Two Digits
1
Give reasoning, not just computation: Compute the remainder when $35^89$ is divided by $100$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or...
[ { "method_name": "Repeated Squaring", "approach": "Use exponentiation by squaring to compute $a^b\\bmod m$ efficiently, reducing modulo $m$ after each multiplication.", "steps": [ "Step 1: Work modulo 100 throughout; replace $a$ by $a\\bmod 100$ to start.", "Step 2: Compute successive square...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{75}$.\nBoth methods compute the same residue class of $a^b$ modulo 100: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yi...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Key idea: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small. (Here the result is $\boxed{75}$.)
math-001222
Discrete Math: Modular Computation — Avoid Huge Integers
1
Provide a rigorous solution: Compute the remainder when $3^38$ is divided by $10$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mod 5/mod ...
[ { "method_name": "Residue Cycle / Euler–Totient Heuristic", "approach": "Use that residues modulo $m$ often repeat with a period; for $m\\in\\{10,20,100\\}$, last-digit/two-digit cycles are short and can be tracked explicitly.", "steps": [ "Step 1: Consider the sequence $a^1\\bmod 10, a^2\\bmod 10...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{9}$.\nBoth methods compute the same residue class of $a^b$ modulo 10: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yield remainder 9.", "rob...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Takeaway: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small.
math-001223
Number Theory: Congruences — Efficient Exponentiation
1
Solve and justify each step: Compute the remainder when $90^50$ is divided by $20$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mod 5/mod...
[ { "method_name": "Repeated Squaring", "approach": "Use exponentiation by squaring to compute $a^b\\bmod m$ efficiently, reducing modulo $m$ after each multiplication.", "steps": [ "Step 1: Work modulo 20 throughout; replace $a$ by $a\\bmod 20$ to start.", "Step 2: Compute successive squares ...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{0}$.\nBoth methods compute the same residue class of $a^b$ modulo 20: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yield remainder 0.", "rob...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Core principle: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small.
math-001224
Number Theory: Congruences — Efficient Exponentiation
1
Explain why your operations are valid: Compute the remainder when $20^119$ is divided by $20$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity o...
[ { "method_name": "Repeated Squaring", "approach": "Use exponentiation by squaring to compute $a^b\\bmod m$ efficiently, reducing modulo $m$ after each multiplication.", "steps": [ "Step 1: Work modulo 20 throughout; replace $a$ by $a\\bmod 20$ to start.", "Step 2: Compute successive squares ...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{0}$.\nBoth methods compute the same residue class of $a^b$ modulo 20: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yiel...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Key idea: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small. (Here the result is $\boxed{0}$.)
math-001225
Number Theory: Modular Arithmetic — Repeated Squaring
1
Start by stating any domain restrictions: Compute the remainder when $6^194$ is divided by $100$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parit...
[ { "method_name": "Residue Cycle / Euler–Totient Heuristic", "approach": "Use that residues modulo $m$ often repeat with a period; for $m\\in\\{10,20,100\\}$, last-digit/two-digit cycles are short and can be tracked explicitly.", "steps": [ "Step 1: Consider the sequence $a^1\\bmod 100, a^2\\bmod 1...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{96}$.\nBoth methods compute the same residue class of $a^b$ modulo 100: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yield remainder 96.", "...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Core principle: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small.
math-001226
Number Theory: Modular Arithmetic — Cycles and Periods
1
Track units/moduli carefully: Compute the remainder when $18^176$ is divided by $100$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mod 5/...
[ { "method_name": "Repeated Squaring", "approach": "Use exponentiation by squaring to compute $a^b\\bmod m$ efficiently, reducing modulo $m$ after each multiplication.", "steps": [ "Step 1: Work modulo 100 throughout; replace $a$ by $a\\bmod 100$ to start.", "Step 2: Compute successive square...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{76}$.\nBoth methods compute the same residue class of $a^b$ modulo 100: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Core principle: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small.
math-001227
Number Theory: Modular Arithmetic — Repeated Squaring
1
Exercise: Compute the remainder when $84^201$ is divided by $20$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mod 5/mod 4 reasoning). Yo...
[ { "method_name": "Repeated Squaring", "approach": "Use exponentiation by squaring to compute $a^b\\bmod m$ efficiently, reducing modulo $m$ after each multiplication.", "steps": [ "Step 1: Work modulo 20 throughout; replace $a$ by $a\\bmod 20$ to start.", "Step 2: Compute successive squares ...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{4}$.\nBoth methods compute the same residue class of $a^b$ modulo 20: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. ...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Core principle: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small.
math-001228
Number Theory: Modular Arithmetic — Cycles and Periods
1
Work carefully and justify each inference: Compute the remainder when $36^94$ is divided by $100$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., pari...
[ { "method_name": "Repeated Squaring", "approach": "Use exponentiation by squaring to compute $a^b\\bmod m$ efficiently, reducing modulo $m$ after each multiplication.", "steps": [ "Step 1: Work modulo 100 throughout; replace $a$ by $a\\bmod 100$ to start.", "Step 2: Compute successive square...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{16}$.\nBoth methods compute the same residue class of $a^b$ modulo 100: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yield remainder 16.", "...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Key idea: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small.
math-001229
Number Theory: Modular Arithmetic — Cycles and Periods
1
Problem: Compute the remainder when $82^103$ is divided by $100$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mod 5/mod 4 reasoning). Yo...
[ { "method_name": "Residue Cycle / Euler–Totient Heuristic", "approach": "Use that residues modulo $m$ often repeat with a period; for $m\\in\\{10,20,100\\}$, last-digit/two-digit cycles are short and can be tracked explicitly.", "steps": [ "Step 1: Consider the sequence $a^1\\bmod 100, a^2\\bmod 1...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{68}$.\nBoth methods compute the same residue class of $a^b$ modulo 100: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yield remainder 68.", "...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Takeaway: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small. (Here the result is $\boxed{68}$.)
math-001230
Number Theory: Congruences — Efficient Exponentiation
1
Solve and justify each step: Compute the remainder when $83^93$ is divided by $20$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mod 5/mod...
[ { "method_name": "Residue Cycle / Euler–Totient Heuristic", "approach": "Use that residues modulo $m$ often repeat with a period; for $m\\in\\{10,20,100\\}$, last-digit/two-digit cycles are short and can be tracked explicitly.", "steps": [ "Step 1: Consider the sequence $a^1\\bmod 20, a^2\\bmod 20...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{3}$.\nBoth methods compute the same residue class of $a^b$ modulo 20: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yiel...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Key idea: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small.
math-001231
Number Theory: Modular Arithmetic — Repeated Squaring
1
Find the exact value: Compute the remainder when $38^43$ is divided by $20$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mod 5/mod 4 reas...
[ { "method_name": "Residue Cycle / Euler–Totient Heuristic", "approach": "Use that residues modulo $m$ often repeat with a period; for $m\\in\\{10,20,100\\}$, last-digit/two-digit cycles are short and can be tracked explicitly.", "steps": [ "Step 1: Consider the sequence $a^1\\bmod 20, a^2\\bmod 20...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{12}$.\nBoth methods compute the same residue class of $a^b$ modulo 20: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yield remainder 12.", "r...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Core principle: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small. (Here the result is $\boxed{12}$.)
math-001232
Number Theory: Congruences — Efficient Exponentiation
1
Carefully track domains: Compute the remainder when $54^221$ is divided by $100$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mod 5/mod 4...
[ { "method_name": "Residue Cycle / Euler–Totient Heuristic", "approach": "Use that residues modulo $m$ often repeat with a period; for $m\\in\\{10,20,100\\}$, last-digit/two-digit cycles are short and can be tracked explicitly.", "steps": [ "Step 1: Consider the sequence $a^1\\bmod 100, a^2\\bmod 1...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{4}$.\nBoth methods compute the same residue class of $a^b$ modulo 100: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yie...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Core principle: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small.
math-001233
Number Theory: Modular Arithmetic — Cycles and Periods
1
Solve and justify each step: Compute the remainder when $9^82$ is divided by $100$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mod 5/mod...
[ { "method_name": "Repeated Squaring", "approach": "Use exponentiation by squaring to compute $a^b\\bmod m$ efficiently, reducing modulo $m$ after each multiplication.", "steps": [ "Step 1: Work modulo 100 throughout; replace $a$ by $a\\bmod 100$ to start.", "Step 2: Compute successive square...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{81}$.\nBoth methods compute the same residue class of $a^b$ modulo 100: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yi...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Core principle: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small. (Here the result is $\boxed{81}$.)
math-001234
Number Theory: Residues — Last Digits / Two Digits
1
Work carefully and justify each inference: Compute the remainder when $40^233$ is divided by $20$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., pari...
[ { "method_name": "Residue Cycle / Euler–Totient Heuristic", "approach": "Use that residues modulo $m$ often repeat with a period; for $m\\in\\{10,20,100\\}$, last-digit/two-digit cycles are short and can be tracked explicitly.", "steps": [ "Step 1: Consider the sequence $a^1\\bmod 20, a^2\\bmod 20...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{0}$.\nBoth methods compute the same residue class of $a^b$ modulo 20: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yield remainder 0.", "rob...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Core principle: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small.
math-001235
Number Theory: Modular Arithmetic — Cycles and Periods
1
Explain each transformation: Compute the remainder when $31^101$ is divided by $100$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mod 5/m...
[ { "method_name": "Repeated Squaring", "approach": "Use exponentiation by squaring to compute $a^b\\bmod m$ efficiently, reducing modulo $m$ after each multiplication.", "steps": [ "Step 1: Work modulo 100 throughout; replace $a$ by $a\\bmod 100$ to start.", "Step 2: Compute successive square...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{31}$.\nBoth methods compute the same residue class of $a^b$ modulo 100: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Takeaway: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small. (Here the result is $\boxed{31}$.)
math-001236
Discrete Math: Modular Computation — Avoid Huge Integers
1
Show all reasoning: Compute the remainder when $39^120$ is divided by $20$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mod 5/mod 4 reaso...
[ { "method_name": "Residue Cycle / Euler–Totient Heuristic", "approach": "Use that residues modulo $m$ often repeat with a period; for $m\\in\\{10,20,100\\}$, last-digit/two-digit cycles are short and can be tracked explicitly.", "steps": [ "Step 1: Consider the sequence $a^1\\bmod 20, a^2\\bmod 20...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{1}$.\nBoth methods compute the same residue class of $a^b$ modulo 20: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yield remainder 1.", ...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Core principle: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small. (Here the result is $\boxed{1}$.)
math-001237
Number Theory: Residues — Last Digits / Two Digits
1
Try to avoid pattern-matching; explain why: Compute the remainder when $27^179$ is divided by $10$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., par...
[ { "method_name": "Residue Cycle / Euler–Totient Heuristic", "approach": "Use that residues modulo $m$ often repeat with a period; for $m\\in\\{10,20,100\\}$, last-digit/two-digit cycles are short and can be tracked explicitly.", "steps": [ "Step 1: Consider the sequence $a^1\\bmod 10, a^2\\bmod 10...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{3}$.\nBoth methods compute the same residue class of $a^b$ modulo 10: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yield remainder 3.", ...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Takeaway: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small. (Here the result is $\boxed{3}$.)
math-001238
Discrete Math: Modular Computation — Avoid Huge Integers
1
Keep the final answer in boxed form: Compute the remainder when $4^89$ is divided by $10$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mo...
[ { "method_name": "Residue Cycle / Euler–Totient Heuristic", "approach": "Use that residues modulo $m$ often repeat with a period; for $m\\in\\{10,20,100\\}$, last-digit/two-digit cycles are short and can be tracked explicitly.", "steps": [ "Step 1: Consider the sequence $a^1\\bmod 10, a^2\\bmod 10...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{4}$.\nBoth methods compute the same residue class of $a^b$ modulo 10: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yield remainder 4.", "rob...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Takeaway: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small. (Here the result is $\boxed{4}$.)
math-001239
Number Theory: Residues — Last Digits / Two Digits
1
Track units/moduli carefully: Compute the remainder when $86^43$ is divided by $10$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mod 5/mo...
[ { "method_name": "Repeated Squaring", "approach": "Use exponentiation by squaring to compute $a^b\\bmod m$ efficiently, reducing modulo $m$ after each multiplication.", "steps": [ "Step 1: Work modulo 10 throughout; replace $a$ by $a\\bmod 10$ to start.", "Step 2: Compute successive squares ...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{6}$.\nBoth methods compute the same residue class of $a^b$ modulo 10: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yiel...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Key idea: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small. (Here the result is $\boxed{6}$.)
math-001240
Discrete Math: Modular Computation — Avoid Huge Integers
1
Give a theorem-based solution: Compute the remainder when $45^123$ is divided by $100$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mod 5...
[ { "method_name": "Residue Cycle / Euler–Totient Heuristic", "approach": "Use that residues modulo $m$ often repeat with a period; for $m\\in\\{10,20,100\\}$, last-digit/two-digit cycles are short and can be tracked explicitly.", "steps": [ "Step 1: Consider the sequence $a^1\\bmod 100, a^2\\bmod 1...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{25}$.\nBoth methods compute the same residue class of $a^b$ modulo 100: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Takeaway: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small.
math-001241
Discrete Math: Modular Computation — Avoid Huge Integers
1
Keep the final answer in boxed form: Compute the remainder when $38^203$ is divided by $20$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or ...
[ { "method_name": "Repeated Squaring", "approach": "Use exponentiation by squaring to compute $a^b\\bmod m$ efficiently, reducing modulo $m$ after each multiplication.", "steps": [ "Step 1: Work modulo 20 throughout; replace $a$ by $a\\bmod 20$ to start.", "Step 2: Compute successive squares ...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{12}$.\nBoth methods compute the same residue class of $a^b$ modulo 20: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yield remainder 12.", "r...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Remember: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small. (Here the result is $\boxed{12}$.)
math-001242
Number Theory: Residues — Last Digits / Two Digits
1
Keep the final answer in boxed form: Compute the remainder when $71^61$ is divided by $20$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or m...
[ { "method_name": "Repeated Squaring", "approach": "Use exponentiation by squaring to compute $a^b\\bmod m$ efficiently, reducing modulo $m$ after each multiplication.", "steps": [ "Step 1: Work modulo 20 throughout; replace $a$ by $a\\bmod 20$ to start.", "Step 2: Compute successive squares ...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{11}$.\nBoth methods compute the same residue class of $a^b$ modulo 20: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yield remainder 11."...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Key idea: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small.
math-001243
Number Theory: Modular Arithmetic — Cycles and Periods
1
Determine the requested value: Compute the remainder when $96^53$ is divided by $20$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mod 5/m...
[ { "method_name": "Residue Cycle / Euler–Totient Heuristic", "approach": "Use that residues modulo $m$ often repeat with a period; for $m\\in\\{10,20,100\\}$, last-digit/two-digit cycles are short and can be tracked explicitly.", "steps": [ "Step 1: Consider the sequence $a^1\\bmod 20, a^2\\bmod 20...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{16}$.\nBoth methods compute the same residue class of $a^b$ modulo 20: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity....
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Remember: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small. (Here the result is $\boxed{16}$.)
math-001244
Discrete Math: Modular Computation — Avoid Huge Integers
1
Work carefully and justify each inference: Compute the remainder when $89^17$ is divided by $10$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parit...
[ { "method_name": "Residue Cycle / Euler–Totient Heuristic", "approach": "Use that residues modulo $m$ often repeat with a period; for $m\\in\\{10,20,100\\}$, last-digit/two-digit cycles are short and can be tracked explicitly.", "steps": [ "Step 1: Consider the sequence $a^1\\bmod 10, a^2\\bmod 10...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{9}$.\nBoth methods compute the same residue class of $a^b$ modulo 10: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yield remainder 9.", "rob...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Takeaway: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small.
math-001245
Discrete Math: Modular Computation — Avoid Huge Integers
1
Checkpoint: Compute the remainder when $28^63$ is divided by $10$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mod 5/mod 4 reasoning). Y...
[ { "method_name": "Residue Cycle / Euler–Totient Heuristic", "approach": "Use that residues modulo $m$ often repeat with a period; for $m\\in\\{10,20,100\\}$, last-digit/two-digit cycles are short and can be tracked explicitly.", "steps": [ "Step 1: Consider the sequence $a^1\\bmod 10, a^2\\bmod 10...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{2}$.\nBoth methods compute the same residue class of $a^b$ modulo 10: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. ...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Takeaway: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small.
math-001246
Number Theory: Residues — Last Digits / Two Digits
1
Derive the result step-by-step: Compute the remainder when $61^250$ is divided by $10$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mod 5...
[ { "method_name": "Repeated Squaring", "approach": "Use exponentiation by squaring to compute $a^b\\bmod m$ efficiently, reducing modulo $m$ after each multiplication.", "steps": [ "Step 1: Work modulo 10 throughout; replace $a$ by $a\\bmod 10$ to start.", "Step 2: Compute successive squares ...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{1}$.\nBoth methods compute the same residue class of $a^b$ modulo 10: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. ...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Takeaway: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small.
math-001247
Number Theory: Congruences — Efficient Exponentiation
1
Explain why your operations are valid: Compute the remainder when $76^57$ is divided by $20$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or...
[ { "method_name": "Residue Cycle / Euler–Totient Heuristic", "approach": "Use that residues modulo $m$ often repeat with a period; for $m\\in\\{10,20,100\\}$, last-digit/two-digit cycles are short and can be tracked explicitly.", "steps": [ "Step 1: Consider the sequence $a^1\\bmod 20, a^2\\bmod 20...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{16}$.\nBoth methods compute the same residue class of $a^b$ modulo 20: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yield remainder 16.", "r...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Core principle: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small. (Here the result is $\boxed{16}$.)
math-001248
Number Theory: Residues — Last Digits / Two Digits
1
Explain each transformation: Compute the remainder when $53^70$ is divided by $10$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mod 5/mod...
[ { "method_name": "Residue Cycle / Euler–Totient Heuristic", "approach": "Use that residues modulo $m$ often repeat with a period; for $m\\in\\{10,20,100\\}$, last-digit/two-digit cycles are short and can be tracked explicitly.", "steps": [ "Step 1: Consider the sequence $a^1\\bmod 10, a^2\\bmod 10...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{9}$.\nBoth methods compute the same residue class of $a^b$ modulo 10: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yield remainder 9.", ...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Core principle: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small.
math-001249
Number Theory: Congruences — Efficient Exponentiation
1
Provide both a computational and a conceptual explanation: Compute the remainder when $67^241$ is divided by $20$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency c...
[ { "method_name": "Repeated Squaring", "approach": "Use exponentiation by squaring to compute $a^b\\bmod m$ efficiently, reducing modulo $m$ after each multiplication.", "steps": [ "Step 1: Work modulo 20 throughout; replace $a$ by $a\\bmod 20$ to start.", "Step 2: Compute successive squares ...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{7}$.\nBoth methods compute the same residue class of $a^b$ modulo 20: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yiel...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Takeaway: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small.
math-001250
Number Theory: Modular Arithmetic — Cycles and Periods
1
Give an answer and a quick verification: Compute the remainder when $33^92$ is divided by $20$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity ...
[ { "method_name": "Repeated Squaring", "approach": "Use exponentiation by squaring to compute $a^b\\bmod m$ efficiently, reducing modulo $m$ after each multiplication.", "steps": [ "Step 1: Work modulo 20 throughout; replace $a$ by $a\\bmod 20$ to start.", "Step 2: Compute successive squares ...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{1}$.\nBoth methods compute the same residue class of $a^b$ modulo 20: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yiel...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Remember: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small.
math-001251
Number Theory: Residues — Last Digits / Two Digits
1
Start by stating any domain restrictions: Compute the remainder when $35^56$ is divided by $20$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity...
[ { "method_name": "Repeated Squaring", "approach": "Use exponentiation by squaring to compute $a^b\\bmod m$ efficiently, reducing modulo $m$ after each multiplication.", "steps": [ "Step 1: Work modulo 20 throughout; replace $a$ by $a\\bmod 20$ to start.", "Step 2: Compute successive squares ...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{5}$.\nBoth methods compute the same residue class of $a^b$ modulo 20: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. ...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Takeaway: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small.
math-001252
Discrete Math: Modular Computation — Avoid Huge Integers
1
Answer using clear logical steps: Compute the remainder when $54^223$ is divided by $10$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mod...
[ { "method_name": "Repeated Squaring", "approach": "Use exponentiation by squaring to compute $a^b\\bmod m$ efficiently, reducing modulo $m$ after each multiplication.", "steps": [ "Step 1: Work modulo 10 throughout; replace $a$ by $a\\bmod 10$ to start.", "Step 2: Compute successive squares ...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{4}$.\nBoth methods compute the same residue class of $a^b$ modulo 10: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yiel...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Core principle: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small.
math-001253
Number Theory: Congruences — Efficient Exponentiation
1
Write the solution set clearly: Compute the remainder when $85^107$ is divided by $10$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mod 5...
[ { "method_name": "Repeated Squaring", "approach": "Use exponentiation by squaring to compute $a^b\\bmod m$ efficiently, reducing modulo $m$ after each multiplication.", "steps": [ "Step 1: Work modulo 10 throughout; replace $a$ by $a\\bmod 10$ to start.", "Step 2: Compute successive squares ...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{5}$.\nBoth methods compute the same residue class of $a^b$ modulo 10: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yiel...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Takeaway: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small. (Here the result is $\boxed{5}$.)
math-001254
Number Theory: Modular Arithmetic — Repeated Squaring
1
Solve and include a self-check: Compute the remainder when $50^148$ is divided by $10$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mod 5...
[ { "method_name": "Residue Cycle / Euler–Totient Heuristic", "approach": "Use that residues modulo $m$ often repeat with a period; for $m\\in\\{10,20,100\\}$, last-digit/two-digit cycles are short and can be tracked explicitly.", "steps": [ "Step 1: Consider the sequence $a^1\\bmod 10, a^2\\bmod 10...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{0}$.\nBoth methods compute the same residue class of $a^b$ modulo 10: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. ...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Remember: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small.
math-001255
Number Theory: Residues — Last Digits / Two Digits
1
Solve and then verify: Compute the remainder when $25^241$ is divided by $100$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mod 5/mod 4 r...
[ { "method_name": "Repeated Squaring", "approach": "Use exponentiation by squaring to compute $a^b\\bmod m$ efficiently, reducing modulo $m$ after each multiplication.", "steps": [ "Step 1: Work modulo 100 throughout; replace $a$ by $a\\bmod 100$ to start.", "Step 2: Compute successive square...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{25}$.\nBoth methods compute the same residue class of $a^b$ modulo 100: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yield remainder 25.", "...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Remember: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small.
math-001256
Discrete Math: Modular Computation — Avoid Huge Integers
1
Track quantifiers carefully: Compute the remainder when $24^73$ is divided by $100$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mod 5/mo...
[ { "method_name": "Residue Cycle / Euler–Totient Heuristic", "approach": "Use that residues modulo $m$ often repeat with a period; for $m\\in\\{10,20,100\\}$, last-digit/two-digit cycles are short and can be tracked explicitly.", "steps": [ "Step 1: Consider the sequence $a^1\\bmod 100, a^2\\bmod 1...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{24}$.\nBoth methods compute the same residue class of $a^b$ modulo 100: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yield remainder 24.", "...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Core principle: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small.
math-001257
Number Theory: Modular Arithmetic — Repeated Squaring
1
Make each step logically reversible (or explain if not): Compute the remainder when $4^149$ is divided by $100$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency che...
[ { "method_name": "Residue Cycle / Euler–Totient Heuristic", "approach": "Use that residues modulo $m$ often repeat with a period; for $m\\in\\{10,20,100\\}$, last-digit/two-digit cycles are short and can be tracked explicitly.", "steps": [ "Step 1: Consider the sequence $a^1\\bmod 100, a^2\\bmod 1...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{44}$.\nBoth methods compute the same residue class of $a^b$ modulo 100: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yield remainder 44....
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Takeaway: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small. (Here the result is $\boxed{44}$.)
math-001258
Discrete Math: Modular Computation — Avoid Huge Integers
1
Problem: Compute the remainder when $81^21$ is divided by $20$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mod 5/mod 4 reasoning). Your...
[ { "method_name": "Repeated Squaring", "approach": "Use exponentiation by squaring to compute $a^b\\bmod m$ efficiently, reducing modulo $m$ after each multiplication.", "steps": [ "Step 1: Work modulo 20 throughout; replace $a$ by $a\\bmod 20$ to start.", "Step 2: Compute successive squares ...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{1}$.\nBoth methods compute the same residue class of $a^b$ modulo 20: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. ...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Remember: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small. (Here the result is $\boxed{1}$.)
math-001259
Number Theory: Residues — Last Digits / Two Digits
1
Challenge: Compute the remainder when $2^45$ is divided by $100$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mod 5/mod 4 reasoning). Yo...
[ { "method_name": "Repeated Squaring", "approach": "Use exponentiation by squaring to compute $a^b\\bmod m$ efficiently, reducing modulo $m$ after each multiplication.", "steps": [ "Step 1: Work modulo 100 throughout; replace $a$ by $a\\bmod 100$ to start.", "Step 2: Compute successive square...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{32}$.\nBoth methods compute the same residue class of $a^b$ modulo 100: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yield remainder 32.", "...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Core principle: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small. (Here the result is $\boxed{32}$.)
math-001260
Discrete Math: Modular Computation — Avoid Huge Integers
1
Task: Compute the remainder when $54^71$ is divided by $10$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mod 5/mod 4 reasoning). Your wo...
[ { "method_name": "Residue Cycle / Euler–Totient Heuristic", "approach": "Use that residues modulo $m$ often repeat with a period; for $m\\in\\{10,20,100\\}$, last-digit/two-digit cycles are short and can be tracked explicitly.", "steps": [ "Step 1: Consider the sequence $a^1\\bmod 10, a^2\\bmod 10...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{4}$.\nBoth methods compute the same residue class of $a^b$ modulo 10: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yiel...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Takeaway: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small. (Here the result is $\boxed{4}$.)
math-001261
Discrete Math: Modular Computation — Avoid Huge Integers
1
Answer using clear logical steps: Compute the remainder when $42^102$ is divided by $100$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mo...
[ { "method_name": "Residue Cycle / Euler–Totient Heuristic", "approach": "Use that residues modulo $m$ often repeat with a period; for $m\\in\\{10,20,100\\}$, last-digit/two-digit cycles are short and can be tracked explicitly.", "steps": [ "Step 1: Consider the sequence $a^1\\bmod 100, a^2\\bmod 1...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{64}$.\nBoth methods compute the same residue class of $a^b$ modulo 100: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yield remainder 64.", "...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Takeaway: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small. (Here the result is $\boxed{64}$.)
math-001262
Number Theory: Congruences — Efficient Exponentiation
1
Work carefully and justify each inference: Compute the remainder when $48^226$ is divided by $100$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., par...
[ { "method_name": "Residue Cycle / Euler–Totient Heuristic", "approach": "Use that residues modulo $m$ often repeat with a period; for $m\\in\\{10,20,100\\}$, last-digit/two-digit cycles are short and can be tracked explicitly.", "steps": [ "Step 1: Consider the sequence $a^1\\bmod 100, a^2\\bmod 1...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{64}$.\nBoth methods compute the same residue class of $a^b$ modulo 100: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yield remainder 64....
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Takeaway: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small. (Here the result is $\boxed{64}$.)
math-001263
Discrete Math: Modular Computation — Avoid Huge Integers
1
Derive the result step-by-step: Compute the remainder when $78^4$ is divided by $10$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mod 5/m...
[ { "method_name": "Repeated Squaring", "approach": "Use exponentiation by squaring to compute $a^b\\bmod m$ efficiently, reducing modulo $m$ after each multiplication.", "steps": [ "Step 1: Work modulo 10 throughout; replace $a$ by $a\\bmod 10$ to start.", "Step 2: Compute successive squares ...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{6}$.\nBoth methods compute the same residue class of $a^b$ modulo 10: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yield remainder 6.", ...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Takeaway: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small. (Here the result is $\boxed{6}$.)
math-001264
Number Theory: Modular Arithmetic — Repeated Squaring
1
Answer with a short justification: Compute the remainder when $13^105$ is divided by $100$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or m...
[ { "method_name": "Residue Cycle / Euler–Totient Heuristic", "approach": "Use that residues modulo $m$ often repeat with a period; for $m\\in\\{10,20,100\\}$, last-digit/two-digit cycles are short and can be tracked explicitly.", "steps": [ "Step 1: Consider the sequence $a^1\\bmod 100, a^2\\bmod 1...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{93}$.\nBoth methods compute the same residue class of $a^b$ modulo 100: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yield remainder 93.", "...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Key idea: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small.
math-001265
Number Theory: Modular Arithmetic — Repeated Squaring
1
Track quantifiers carefully: Compute the remainder when $99^5$ is divided by $10$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mod 5/mod ...
[ { "method_name": "Repeated Squaring", "approach": "Use exponentiation by squaring to compute $a^b\\bmod m$ efficiently, reducing modulo $m$ after each multiplication.", "steps": [ "Step 1: Work modulo 10 throughout; replace $a$ by $a\\bmod 10$ to start.", "Step 2: Compute successive squares ...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{9}$.\nBoth methods compute the same residue class of $a^b$ modulo 10: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. ...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Key idea: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small. (Here the result is $\boxed{9}$.)
math-001266
Number Theory: Congruences — Efficient Exponentiation
1
Determine the requested value: Compute the remainder when $50^103$ is divided by $100$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mod 5...
[ { "method_name": "Repeated Squaring", "approach": "Use exponentiation by squaring to compute $a^b\\bmod m$ efficiently, reducing modulo $m$ after each multiplication.", "steps": [ "Step 1: Work modulo 100 throughout; replace $a$ by $a\\bmod 100$ to start.", "Step 2: Compute successive square...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{0}$.\nBoth methods compute the same residue class of $a^b$ modulo 100: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yield remainder 0.",...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Key idea: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small. (Here the result is $\boxed{0}$.)
math-001267
Number Theory: Residues — Last Digits / Two Digits
1
Prompt: Compute the remainder when $26^174$ is divided by $20$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mod 5/mod 4 reasoning). Your...
[ { "method_name": "Residue Cycle / Euler–Totient Heuristic", "approach": "Use that residues modulo $m$ often repeat with a period; for $m\\in\\{10,20,100\\}$, last-digit/two-digit cycles are short and can be tracked explicitly.", "steps": [ "Step 1: Consider the sequence $a^1\\bmod 20, a^2\\bmod 20...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{16}$.\nBoth methods compute the same residue class of $a^b$ modulo 20: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yie...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Core principle: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small. (Here the result is $\boxed{16}$.)
math-001268
Number Theory: Modular Arithmetic — Repeated Squaring
1
Track quantifiers carefully: Compute the remainder when $20^90$ is divided by $100$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mod 5/mo...
[ { "method_name": "Residue Cycle / Euler–Totient Heuristic", "approach": "Use that residues modulo $m$ often repeat with a period; for $m\\in\\{10,20,100\\}$, last-digit/two-digit cycles are short and can be tracked explicitly.", "steps": [ "Step 1: Consider the sequence $a^1\\bmod 100, a^2\\bmod 1...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{0}$.\nBoth methods compute the same residue class of $a^b$ modulo 100: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yield remainder 0.",...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Key idea: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small. (Here the result is $\boxed{0}$.)
math-001269
Number Theory: Congruences — Efficient Exponentiation
1
Give reasoning, not just computation: Compute the remainder when $45^190$ is divided by $20$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or...
[ { "method_name": "Residue Cycle / Euler–Totient Heuristic", "approach": "Use that residues modulo $m$ often repeat with a period; for $m\\in\\{10,20,100\\}$, last-digit/two-digit cycles are short and can be tracked explicitly.", "steps": [ "Step 1: Consider the sequence $a^1\\bmod 20, a^2\\bmod 20...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{5}$.\nBoth methods compute the same residue class of $a^b$ modulo 20: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yield remainder 5.", ...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Core principle: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small.
math-001270
Number Theory: Congruences — Efficient Exponentiation
1
Give a theorem-based solution: Compute the remainder when $9^51$ is divided by $20$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mod 5/mo...
[ { "method_name": "Residue Cycle / Euler–Totient Heuristic", "approach": "Use that residues modulo $m$ often repeat with a period; for $m\\in\\{10,20,100\\}$, last-digit/two-digit cycles are short and can be tracked explicitly.", "steps": [ "Step 1: Consider the sequence $a^1\\bmod 20, a^2\\bmod 20...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{9}$.\nBoth methods compute the same residue class of $a^b$ modulo 20: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. ...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Key idea: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small.
math-001271
Number Theory: Residues — Last Digits / Two Digits
1
Answer using clear logical steps: Compute the remainder when $49^181$ is divided by $20$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mod...
[ { "method_name": "Residue Cycle / Euler–Totient Heuristic", "approach": "Use that residues modulo $m$ often repeat with a period; for $m\\in\\{10,20,100\\}$, last-digit/two-digit cycles are short and can be tracked explicitly.", "steps": [ "Step 1: Consider the sequence $a^1\\bmod 20, a^2\\bmod 20...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{9}$.\nBoth methods compute the same residue class of $a^b$ modulo 20: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yield remainder 9.", "rob...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Core principle: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small. (Here the result is $\boxed{9}$.)
math-001272
Number Theory: Congruences — Efficient Exponentiation
1
Track quantifiers carefully: Compute the remainder when $72^49$ is divided by $10$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mod 5/mod...
[ { "method_name": "Repeated Squaring", "approach": "Use exponentiation by squaring to compute $a^b\\bmod m$ efficiently, reducing modulo $m$ after each multiplication.", "steps": [ "Step 1: Work modulo 10 throughout; replace $a$ by $a\\bmod 10$ to start.", "Step 2: Compute successive squares ...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{2}$.\nBoth methods compute the same residue class of $a^b$ modulo 10: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yield remainder 2.", "rob...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Core principle: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small.
math-001273
Discrete Math: Modular Computation — Avoid Huge Integers
1
Try to avoid pattern-matching; explain why: Compute the remainder when $98^94$ is divided by $20$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., pari...
[ { "method_name": "Repeated Squaring", "approach": "Use exponentiation by squaring to compute $a^b\\bmod m$ efficiently, reducing modulo $m$ after each multiplication.", "steps": [ "Step 1: Work modulo 20 throughout; replace $a$ by $a\\bmod 20$ to start.", "Step 2: Compute successive squares ...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{4}$.\nBoth methods compute the same residue class of $a^b$ modulo 20: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. ...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Takeaway: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small. (Here the result is $\boxed{4}$.)
math-001274
Discrete Math: Modular Computation — Avoid Huge Integers
1
Start by stating any domain restrictions: Compute the remainder when $83^165$ is divided by $10$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parit...
[ { "method_name": "Residue Cycle / Euler–Totient Heuristic", "approach": "Use that residues modulo $m$ often repeat with a period; for $m\\in\\{10,20,100\\}$, last-digit/two-digit cycles are short and can be tracked explicitly.", "steps": [ "Step 1: Consider the sequence $a^1\\bmod 10, a^2\\bmod 10...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{3}$.\nBoth methods compute the same residue class of $a^b$ modulo 10: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yield remainder 3.", "rob...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Remember: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small. (Here the result is $\boxed{3}$.)
math-001275
Number Theory: Modular Arithmetic — Repeated Squaring
1
Make each step logically reversible (or explain if not): Compute the remainder when $95^61$ is divided by $20$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency chec...
[ { "method_name": "Residue Cycle / Euler–Totient Heuristic", "approach": "Use that residues modulo $m$ often repeat with a period; for $m\\in\\{10,20,100\\}$, last-digit/two-digit cycles are short and can be tracked explicitly.", "steps": [ "Step 1: Consider the sequence $a^1\\bmod 20, a^2\\bmod 20...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{15}$.\nBoth methods compute the same residue class of $a^b$ modulo 20: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yield remainder 15.", "r...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Remember: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small. (Here the result is $\boxed{15}$.)
math-001276
Number Theory: Modular Arithmetic — Repeated Squaring
1
Where appropriate, name the theorem you use: Compute the remainder when $35^242$ is divided by $100$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., p...
[ { "method_name": "Repeated Squaring", "approach": "Use exponentiation by squaring to compute $a^b\\bmod m$ efficiently, reducing modulo $m$ after each multiplication.", "steps": [ "Step 1: Work modulo 100 throughout; replace $a$ by $a\\bmod 100$ to start.", "Step 2: Compute successive square...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{25}$.\nBoth methods compute the same residue class of $a^b$ modulo 100: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yield remainder 25.", "...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Core principle: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small.
math-001277
Discrete Math: Modular Computation — Avoid Huge Integers
1
Write the solution set clearly: Compute the remainder when $78^107$ is divided by $10$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mod 5...
[ { "method_name": "Residue Cycle / Euler–Totient Heuristic", "approach": "Use that residues modulo $m$ often repeat with a period; for $m\\in\\{10,20,100\\}$, last-digit/two-digit cycles are short and can be tracked explicitly.", "steps": [ "Step 1: Consider the sequence $a^1\\bmod 10, a^2\\bmod 10...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{2}$.\nBoth methods compute the same residue class of $a^b$ modulo 10: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yield remainder 2.", "rob...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Takeaway: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small.
math-001278
Number Theory: Modular Arithmetic — Repeated Squaring
1
Warm-up: Compute the remainder when $57^133$ is divided by $100$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mod 5/mod 4 reasoning). Yo...
[ { "method_name": "Repeated Squaring", "approach": "Use exponentiation by squaring to compute $a^b\\bmod m$ efficiently, reducing modulo $m$ after each multiplication.", "steps": [ "Step 1: Work modulo 100 throughout; replace $a$ by $a\\bmod 100$ to start.", "Step 2: Compute successive square...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{57}$.\nBoth methods compute the same residue class of $a^b$ modulo 100: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Core principle: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small. (Here the result is $\boxed{57}$.)
math-001279
Number Theory: Congruences — Efficient Exponentiation
1
Solve and sanity-check: Compute the remainder when $21^238$ is divided by $100$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mod 5/mod 4 ...
[ { "method_name": "Residue Cycle / Euler–Totient Heuristic", "approach": "Use that residues modulo $m$ often repeat with a period; for $m\\in\\{10,20,100\\}$, last-digit/two-digit cycles are short and can be tracked explicitly.", "steps": [ "Step 1: Consider the sequence $a^1\\bmod 100, a^2\\bmod 1...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{61}$.\nBoth methods compute the same residue class of $a^b$ modulo 100: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yi...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Key idea: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small. (Here the result is $\boxed{61}$.)
math-001280
Discrete Math: Modular Computation — Avoid Huge Integers
1
Solve and justify each step: Compute the remainder when $60^60$ is divided by $100$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mod 5/mo...
[ { "method_name": "Repeated Squaring", "approach": "Use exponentiation by squaring to compute $a^b\\bmod m$ efficiently, reducing modulo $m$ after each multiplication.", "steps": [ "Step 1: Work modulo 100 throughout; replace $a$ by $a\\bmod 100$ to start.", "Step 2: Compute successive square...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{0}$.\nBoth methods compute the same residue class of $a^b$ modulo 100: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity....
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Key idea: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small. (Here the result is $\boxed{0}$.)
math-001281
Number Theory: Congruences — Efficient Exponentiation
1
Checkpoint: Compute the remainder when $14^186$ is divided by $10$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mod 5/mod 4 reasoning). ...
[ { "method_name": "Repeated Squaring", "approach": "Use exponentiation by squaring to compute $a^b\\bmod m$ efficiently, reducing modulo $m$ after each multiplication.", "steps": [ "Step 1: Work modulo 10 throughout; replace $a$ by $a\\bmod 10$ to start.", "Step 2: Compute successive squares ...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{6}$.\nBoth methods compute the same residue class of $a^b$ modulo 10: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. ...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Core principle: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small. (Here the result is $\boxed{6}$.)
math-001282
Number Theory: Modular Arithmetic — Repeated Squaring
1
Use two approaches if possible: Compute the remainder when $11^226$ is divided by $10$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mod 5...
[ { "method_name": "Residue Cycle / Euler–Totient Heuristic", "approach": "Use that residues modulo $m$ often repeat with a period; for $m\\in\\{10,20,100\\}$, last-digit/two-digit cycles are short and can be tracked explicitly.", "steps": [ "Step 1: Consider the sequence $a^1\\bmod 10, a^2\\bmod 10...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{1}$.\nBoth methods compute the same residue class of $a^b$ modulo 10: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. ...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Remember: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small. (Here the result is $\boxed{1}$.)
math-001283
Number Theory: Congruences — Efficient Exponentiation
1
Compute the requested quantity: Compute the remainder when $72^232$ is divided by $100$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mod ...
[ { "method_name": "Repeated Squaring", "approach": "Use exponentiation by squaring to compute $a^b\\bmod m$ efficiently, reducing modulo $m$ after each multiplication.", "steps": [ "Step 1: Work modulo 100 throughout; replace $a$ by $a\\bmod 100$ to start.", "Step 2: Compute successive square...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{16}$.\nBoth methods compute the same residue class of $a^b$ modulo 100: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yield remainder 16....
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Core principle: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small. (Here the result is $\boxed{16}$.)
math-001284
Number Theory: Residues — Last Digits / Two Digits
1
Do not skip justification steps: Compute the remainder when $4^14$ is divided by $10$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mod 5/...
[ { "method_name": "Residue Cycle / Euler–Totient Heuristic", "approach": "Use that residues modulo $m$ often repeat with a period; for $m\\in\\{10,20,100\\}$, last-digit/two-digit cycles are short and can be tracked explicitly.", "steps": [ "Step 1: Consider the sequence $a^1\\bmod 10, a^2\\bmod 10...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{6}$.\nBoth methods compute the same residue class of $a^b$ modulo 10: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. ...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Remember: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small. (Here the result is $\boxed{6}$.)
math-001285
Discrete Math: Modular Computation — Avoid Huge Integers
1
Solve and sanity-check: Compute the remainder when $9^5$ is divided by $20$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mod 5/mod 4 reas...
[ { "method_name": "Residue Cycle / Euler–Totient Heuristic", "approach": "Use that residues modulo $m$ often repeat with a period; for $m\\in\\{10,20,100\\}$, last-digit/two-digit cycles are short and can be tracked explicitly.", "steps": [ "Step 1: Consider the sequence $a^1\\bmod 20, a^2\\bmod 20...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{9}$.\nBoth methods compute the same residue class of $a^b$ modulo 20: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yield remainder 9.", "rob...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Takeaway: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small.
math-001286
Number Theory: Congruences — Efficient Exponentiation
1
Task: Compute the remainder when $93^144$ is divided by $100$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mod 5/mod 4 reasoning). Your ...
[ { "method_name": "Residue Cycle / Euler–Totient Heuristic", "approach": "Use that residues modulo $m$ often repeat with a period; for $m\\in\\{10,20,100\\}$, last-digit/two-digit cycles are short and can be tracked explicitly.", "steps": [ "Step 1: Consider the sequence $a^1\\bmod 100, a^2\\bmod 1...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{1}$.\nBoth methods compute the same residue class of $a^b$ modulo 100: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yield remainder 1.",...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Key idea: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small. (Here the result is $\boxed{1}$.)
math-001287
Discrete Math: Modular Computation — Avoid Huge Integers
1
Proceed methodically: Compute the remainder when $16^135$ is divided by $10$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mod 5/mod 4 rea...
[ { "method_name": "Residue Cycle / Euler–Totient Heuristic", "approach": "Use that residues modulo $m$ often repeat with a period; for $m\\in\\{10,20,100\\}$, last-digit/two-digit cycles are short and can be tracked explicitly.", "steps": [ "Step 1: Consider the sequence $a^1\\bmod 10, a^2\\bmod 10...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{6}$.\nBoth methods compute the same residue class of $a^b$ modulo 10: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yiel...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Takeaway: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small.
math-001288
Discrete Math: Modular Computation — Avoid Huge Integers
1
Solve and justify each step: Compute the remainder when $56^141$ is divided by $100$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mod 5/m...
[ { "method_name": "Repeated Squaring", "approach": "Use exponentiation by squaring to compute $a^b\\bmod m$ efficiently, reducing modulo $m$ after each multiplication.", "steps": [ "Step 1: Work modulo 100 throughout; replace $a$ by $a\\bmod 100$ to start.", "Step 2: Compute successive square...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{56}$.\nBoth methods compute the same residue class of $a^b$ modulo 100: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Remember: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small.
math-001289
Number Theory: Modular Arithmetic — Repeated Squaring
1
Do not skip justification steps: Compute the remainder when $69^51$ is divided by $100$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mod ...
[ { "method_name": "Residue Cycle / Euler–Totient Heuristic", "approach": "Use that residues modulo $m$ often repeat with a period; for $m\\in\\{10,20,100\\}$, last-digit/two-digit cycles are short and can be tracked explicitly.", "steps": [ "Step 1: Consider the sequence $a^1\\bmod 100, a^2\\bmod 1...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{69}$.\nBoth methods compute the same residue class of $a^b$ modulo 100: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yield remainder 69....
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Core principle: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small. (Here the result is $\boxed{69}$.)
math-001290
Number Theory: Modular Arithmetic — Repeated Squaring
1
Solve with verification: Compute the remainder when $84^67$ is divided by $20$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mod 5/mod 4 r...
[ { "method_name": "Residue Cycle / Euler–Totient Heuristic", "approach": "Use that residues modulo $m$ often repeat with a period; for $m\\in\\{10,20,100\\}$, last-digit/two-digit cycles are short and can be tracked explicitly.", "steps": [ "Step 1: Consider the sequence $a^1\\bmod 20, a^2\\bmod 20...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{4}$.\nBoth methods compute the same residue class of $a^b$ modulo 20: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yield remainder 4.", ...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Remember: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small. (Here the result is $\boxed{4}$.)
math-001291
Discrete Math: Modular Computation — Avoid Huge Integers
1
Explain why your operations are valid: Compute the remainder when $58^86$ is divided by $10$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or...
[ { "method_name": "Residue Cycle / Euler–Totient Heuristic", "approach": "Use that residues modulo $m$ often repeat with a period; for $m\\in\\{10,20,100\\}$, last-digit/two-digit cycles are short and can be tracked explicitly.", "steps": [ "Step 1: Consider the sequence $a^1\\bmod 10, a^2\\bmod 10...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{4}$.\nBoth methods compute the same residue class of $a^b$ modulo 10: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yiel...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Key idea: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small. (Here the result is $\boxed{4}$.)
math-001292
Number Theory: Modular Arithmetic — Repeated Squaring
1
Work carefully and justify each inference: Compute the remainder when $77^3$ is divided by $10$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity...
[ { "method_name": "Repeated Squaring", "approach": "Use exponentiation by squaring to compute $a^b\\bmod m$ efficiently, reducing modulo $m$ after each multiplication.", "steps": [ "Step 1: Work modulo 10 throughout; replace $a$ by $a\\bmod 10$ to start.", "Step 2: Compute successive squares ...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{3}$.\nBoth methods compute the same residue class of $a^b$ modulo 10: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yiel...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Key idea: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small.
math-001293
Number Theory: Residues — Last Digits / Two Digits
1
Warm-up: Compute the remainder when $67^146$ is divided by $100$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mod 5/mod 4 reasoning). Yo...
[ { "method_name": "Repeated Squaring", "approach": "Use exponentiation by squaring to compute $a^b\\bmod m$ efficiently, reducing modulo $m$ after each multiplication.", "steps": [ "Step 1: Work modulo 100 throughout; replace $a$ by $a\\bmod 100$ to start.", "Step 2: Compute successive square...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{69}$.\nBoth methods compute the same residue class of $a^b$ modulo 100: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yi...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Key idea: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small.
math-001294
Number Theory: Modular Arithmetic — Cycles and Periods
1
Work this out carefully: Compute the remainder when $89^5$ is divided by $10$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mod 5/mod 4 re...
[ { "method_name": "Residue Cycle / Euler–Totient Heuristic", "approach": "Use that residues modulo $m$ often repeat with a period; for $m\\in\\{10,20,100\\}$, last-digit/two-digit cycles are short and can be tracked explicitly.", "steps": [ "Step 1: Consider the sequence $a^1\\bmod 10, a^2\\bmod 10...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{9}$.\nBoth methods compute the same residue class of $a^b$ modulo 10: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yield remainder 9.", "rob...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Takeaway: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small. (Here the result is $\boxed{9}$.)
math-001295
Number Theory: Modular Arithmetic — Cycles and Periods
1
Task: Compute the remainder when $37^149$ is divided by $100$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mod 5/mod 4 reasoning). Your ...
[ { "method_name": "Repeated Squaring", "approach": "Use exponentiation by squaring to compute $a^b\\bmod m$ efficiently, reducing modulo $m$ after each multiplication.", "steps": [ "Step 1: Work modulo 100 throughout; replace $a$ by $a\\bmod 100$ to start.", "Step 2: Compute successive square...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{77}$.\nBoth methods compute the same residue class of $a^b$ modulo 100: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yield remainder 77.", "...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Takeaway: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small. (Here the result is $\boxed{77}$.)
math-001296
Number Theory: Modular Arithmetic — Repeated Squaring
1
Make each step logically reversible (or explain if not): Compute the remainder when $41^92$ is divided by $20$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency chec...
[ { "method_name": "Residue Cycle / Euler–Totient Heuristic", "approach": "Use that residues modulo $m$ often repeat with a period; for $m\\in\\{10,20,100\\}$, last-digit/two-digit cycles are short and can be tracked explicitly.", "steps": [ "Step 1: Consider the sequence $a^1\\bmod 20, a^2\\bmod 20...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{1}$.\nBoth methods compute the same residue class of $a^b$ modulo 20: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yield remainder 1.", ...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Core principle: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small. (Here the result is $\boxed{1}$.)
math-001297
Discrete Math: Modular Computation — Avoid Huge Integers
1
Work carefully and justify each inference: Compute the remainder when $60^228$ is divided by $20$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., pari...
[ { "method_name": "Repeated Squaring", "approach": "Use exponentiation by squaring to compute $a^b\\bmod m$ efficiently, reducing modulo $m$ after each multiplication.", "steps": [ "Step 1: Work modulo 20 throughout; replace $a$ by $a\\bmod 20$ to start.", "Step 2: Compute successive squares ...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{0}$.\nBoth methods compute the same residue class of $a^b$ modulo 20: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yiel...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Takeaway: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small.
math-001298
Number Theory: Modular Arithmetic — Cycles and Periods
1
Give a theorem-based solution: Compute the remainder when $26^132$ is divided by $10$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mod 5/...
[ { "method_name": "Repeated Squaring", "approach": "Use exponentiation by squaring to compute $a^b\\bmod m$ efficiently, reducing modulo $m$ after each multiplication.", "steps": [ "Step 1: Work modulo 10 throughout; replace $a$ by $a\\bmod 10$ to start.", "Step 2: Compute successive squares ...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{6}$.\nBoth methods compute the same residue class of $a^b$ modulo 10: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yield remainder 6.", "rob...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Remember: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small. (Here the result is $\boxed{6}$.)
math-001299
Number Theory: Residues — Last Digits / Two Digits
1
Carefully track domains: Compute the remainder when $77^170$ is divided by $20$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mod 5/mod 4 ...
[ { "method_name": "Residue Cycle / Euler–Totient Heuristic", "approach": "Use that residues modulo $m$ often repeat with a period; for $m\\in\\{10,20,100\\}$, last-digit/two-digit cycles are short and can be tracked explicitly.", "steps": [ "Step 1: Consider the sequence $a^1\\bmod 20, a^2\\bmod 20...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{9}$.\nBoth methods compute the same residue class of $a^b$ modulo 20: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity. Both yield remainder 9.", "rob...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Key idea: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small.
math-001300
Number Theory: Congruences — Efficient Exponentiation
1
Answer with a short justification: Compute the remainder when $84^16$ is divided by $100$. (a) Solve using modular reduction and repeated squaring. (b) Solve using a cycle/period argument for residues modulo $m$ (e.g., last-digit cycles). (c) Verify your final remainder by a quick consistency check (e.g., parity or mo...
[ { "method_name": "Residue Cycle / Euler–Totient Heuristic", "approach": "Use that residues modulo $m$ often repeat with a period; for $m\\in\\{10,20,100\\}$, last-digit/two-digit cycles are short and can be tracked explicitly.", "steps": [ "Step 1: Consider the sequence $a^1\\bmod 100, a^2\\bmod 1...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{16}$.\nBoth methods compute the same residue class of $a^b$ modulo 100: repeated squaring is an exact algorithm, and the cycle argument is a conceptual description of the same modular periodicity...
[ { "error_description": "Reduced $a^b$ by reducing $b$ modulo $m$ (e.g., replaced $b$ with $b\\bmod m$).", "why_plausible": "It resembles the valid rule $a\\equiv a'\\pmod m$.", "why_wrong": "Exponents do not reduce modulo $m$ in general; they reduce modulo a period (like $\\varphi(m)$) only under extra ...
Key idea: In modular arithmetic, reduce early and often: compute large powers via repeated squaring, and use periodicity/cycles as a conceptual shortcut when the modulus is small. (Here the result is $\boxed{16}$.)