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A rectangular prism has a volume of \(8 \mathrm{~cm}^{3}\), total surface area of \(32 \mathrm{~cm}^{2}\), and its length, width, and height are in geometric progression. Find the sum of all its edge lengths (in cm).
28
0
5,256.3125
-1
5,256.3125
Square $ABCD$ is constructed along diameter $AB$ of a semicircle, where both the square and semicircle are coplanar. Line segment $AB$ has a length of 8 centimeters. If point $M$ is the midpoint of arc $AB$, what is the length of segment $MD$?
4\sqrt{10}
0
4,393
-1
4,393
Abe holds 1 green and 1 red jelly bean in his hand. Bob holds 1 green, 1 yellow, and 2 red jelly beans in his hand. Each randomly picks a jelly bean to show the other. What is the probability that the colors match?
\frac{3}{8}
1. **Identify the possible outcomes for matching colors**: Abe and Bob can either both show a green jelly bean or both show a red jelly bean. These are the only two scenarios where their jelly bean colors match. 2. **Calculate the probability of both showing a green jelly bean**: - Abe has 1 green jelly bean out of...
0.875
3,403.5625
3,252.357143
4,462
In a lottery game, the host randomly selects one of the four identical empty boxes numbered $1$, $2$, $3$, $4$, puts a prize inside, and then closes all four boxes. The host knows which box contains the prize. When a participant chooses a box, before opening the chosen box, the host randomly opens another box without t...
\frac{1}{3}
0.25
5,920.9375
4,251
6,477.583333
What is the minimum value of $z$ if $z=x^2+2y^2+6x-4y+22?$
11
1
2,004.375
2,004.375
-1
Let $p$ and $q$ be real numbers, and suppose that the roots of the equation \[x^3 - 9x^2 + px - q = 0\] are three distinct positive integers. Compute $p + q.$
38
0
7,913.4375
-1
7,913.4375
A three-digit number has a remainder of 2 when divided by 4, 5, and 6. If three digits are appended to this three-digit number to make it a six-digit number divisible by 4, 5, and 6, what is the smallest six-digit number that meets this condition?
122040
0.0625
8,192
8,192
8,192
Let $A M O L$ be a quadrilateral with $A M=10, M O=11$, and $O L=12$. Given that the perpendicular bisectors of sides $A M$ and $O L$ intersect at the midpoint of segment $A O$, find the length of side LA.
$\sqrt{77}$
Let $D$ be the midpoint of $A M$ and $E$ be the midpoint of $A O$. Then, we note that $A D E \sim A M O$, so $M$ is a right angle. Similarly, $L$ is a right angle. Consequently, we get that $$A O^{2}=O M^{2}+A M^{2} \Rightarrow A L=\sqrt{A O^{2}-O L^{2}}=\sqrt{11^{2}+10^{2}-12^{2}}=\sqrt{77}$$
0
7,952.5625
-1
7,952.5625
Convert the binary number $101101110_{(2)}$ to a decimal number and then to an octal number $({\ }\_{(8)})$.
556_{(8)}
0
4,973.375
-1
4,973.375
The digits of a certain three-digit number form a geometric progression. If the digits of the hundreds and units places are swapped, the new three-digit number will be 594 less than the original number. If, in the original number, the hundreds digit is removed and the remaining two-digit number has its digits swapped,...
842
0.6875
5,430.5
4,175.272727
8,192
Find the value of $c$ such that all the roots of the polynomial $x^3 - 5x^2 + 2bx - c$ are real and positive, given that one root is twice another and four times the third.
\frac{1000}{343}
0.875
4,963.375
4,502.142857
8,192
Triangle $ABC$ has $BC=20.$ The incircle of the triangle evenly trisects the median $AD.$ If the area of the triangle is $m \sqrt{n}$ where $m$ and $n$ are integers and $n$ is not divisible by the square of a prime, find $m+n.$
38
WLOG let E be be between C & D (as in solution 1). Assume $AD = 3m$. We use power of a point to get that $AG = DE = \sqrt{2}m$ and $AB = AG + GB = AG + BE = 10+2\sqrt{2} m$ Since now we have $AC = 10$, $BC = 20, AB = 10+2\sqrt{2} m$ in triangle $\triangle ABC$ and cevian $AD = 3m$. Now, we can apply Stewart's Theorem....
0
8,192
-1
8,192
Points $A$, $B$, $C$, $D$, and $E$ are located in 3-dimensional space with $AB= BC= CD= DE= EA= 2$ and $\angle ABC = \angle CDE = \angle DEA = 90^\circ$. The plane of triangle $ABC$ is parallel to $\overline{DE}$. What is the area of triangle $BDE$?
2
0.1875
8,050.4375
7,437
8,192
Suppose that $x$ and $y$ are real numbers with $-4 \leq x \leq -2$ and $2 \leq y \leq 4$. What is the greatest possible value of $\frac{x+y}{x}$?
\frac{1}{2}
We note that $\frac{x+y}{x} = \frac{x}{x} + \frac{y}{x} = 1 + \frac{y}{x}$. The greatest possible value of $\frac{x+y}{x} = 1 + \frac{y}{x}$ thus occurs when $\frac{y}{x}$ is as great as possible. Since $x$ is always negative and $y$ is always positive, then $\frac{y}{x}$ is negative. Therefore, for $\frac{y}{x}$ to be...
0.75
5,886.3125
5,117.75
8,192
What is the least common multiple of 6, 8, and 10?
120
1
1,839.0625
1,839.0625
-1
When rolling a fair 6-sided die, what is the probability of a 2 or 4 being rolled?
\frac{1}{3}
1
678.1875
678.1875
-1
How many distinct sequences of five letters can be made from the letters in FREQUENCY if each sequence must begin with F, end with Y, and no letter can appear in a sequence more than once? Further, the second letter must be a vowel.
60
0.25
6,938.3125
5,462.25
7,430.333333
If $2x - y = 5$ and $x + 2y = 5$, what is the value of $x$?
3
1
1,729.3125
1,729.3125
-1
In a $3 \times 3$ grid (each cell is a $1 \times 1$ square), two identical pieces are placed, with at most one piece per cell. There are ___ distinct ways to arrange the pieces. (If two arrangements can be made to coincide by rotation, they are considered the same arrangement).
10
0.125
6,793.3125
6,227
6,874.214286
Chelsea goes to La Verde's at MIT and buys 100 coconuts, each weighing 4 pounds, and 100 honeydews, each weighing 5 pounds. She wants to distribute them among \( n \) bags, so that each bag contains at most 13 pounds of fruit. What is the minimum \( n \) for which this is possible?
75
0
8,192
-1
8,192
Using systematic sampling method to select 32 people from 960 for a questionnaire survey, they are randomly numbered from 1 to 960. After grouping, the number drawn by simple random sampling in the first group is 9. Among the 32 people drawn, those with numbers in the interval [1,450] will fill out questionnaire A, tho...
10
0.8125
4,705.8125
4,523.153846
5,497.333333
Given the function $y=\sin (\omega x+\frac{\pi }{3})+2$, its graph shifts to the right by $\frac{4\pi }{3}$ units and coincides with the original graph. Find the minimum value of $|\omega|$.
\frac {3}{2}
0.5
6,759.0625
5,326.125
8,192
Let $u_0 = \frac{1}{3}$, and for $k \ge 0$, let $u_{k+1} = \frac{3}{2}u_k - \frac{3}{2}u_k^2$. This sequence tends to a limit; call it $M$. Determine the least value of $k$ such that $|u_k - M| \le \frac{1}{2^{1000}}$.
10
0
7,281.3125
-1
7,281.3125
Find the interval of all $x$ such that both $2x$ and $3x$ are in the interval $(1,2)$.
\left(\frac{1}{2},\frac{2}{3}\right)
0.9375
2,159.3125
2,152.2
2,266
Today, Ivan the Confessor prefers continuous functions $f:[0,1]\to\mathbb{R}$ satisfying $f(x)+f(y)\geq |x-y|$ for all pairs $x,y\in [0,1]$. Find the minimum of $\int_0^1 f$ over all preferred functions. (
\frac{1}{4}
We are given a continuous function \( f: [0, 1] \to \mathbb{R} \) that satisfies the inequality \( f(x) + f(y) \geq |x-y| \) for all \( x, y \in [0, 1] \). Our goal is to find the minimum value of the integral \(\int_0^1 f(x) \, dx\). ### Step-by-Step Analysis: 1. **Understanding the Inequality:** The condition ...
0
8,069.9375
-1
8,069.9375
What is the largest integer $n$ that satisfies $(100^2-99^2)(99^2-98^2)\dots(3^2-2^2)(2^2-1^2)$ is divisible by $3^n$ ?
49
0.375
7,399.5
6,078.666667
8,192
Given that $(2-x)^{5}=a\_{0}+a\_{1}x+a\_{2}x^{2}+…+a\_{5}x^{5}$, find the value of $\frac{a\_0+a\_2+a\_4}{a\_1+a\_3}$.
-\frac{61}{60}
0.75
5,596.5
4,731.333333
8,192
A circle passing through the vertex \( P \) of triangle \( PQR \) touches side \( QR \) at point \( F \) and intersects sides \( PQ \) and \( PR \) at points \( M \) and \( N \), respectively, different from vertex \( P \). Find the ratio \( QF : FR \) if it is known that the length of side \( PQ \) is 1.5 times the l...
1/2
0.375
6,823.6875
5,335
7,716.9
How many sets of two or more consecutive positive integers have a sum of $15$?
2
1. **Identify the nature of the problem**: We need to find sets of two or more consecutive positive integers that sum to 15. 2. **Formulate the sum of an arithmetic progression (AP)**: The sum of the first $n$ terms of an AP where the first term is $a$ and the common difference is $d=1$ (since the integers are consecu...
0
6,500.625
-1
6,500.625
If a school bus leaves school with 48 students on board, and one-half of the students get off the bus at each of the first three stops, how many students remain on the bus after the third stop?
6
1
1,443.4375
1,443.4375
-1
In an extended game, each of 6 players, including Hugo, rolls a standard 8-sided die. The winner is the one who rolls the highest number. In the case of a tie for the highest roll, the tied players will re-roll until a single winner emerges. What is the probability that Hugo's first roll was a 7, given that he won the ...
\frac{8856}{32768}
0
8,192
-1
8,192
Welcome to the USAYNO, where each question has a yes/no answer. Choose any subset of the following six problems to answer. If you answer $n$ problems and get them all correct, you will receive $\max (0,(n-1)(n-2))$ points. If any of them are wrong, you will receive 0 points. Your answer should be a six-character string...
NNNYYY
Answer: NNNYYY
0
8,034.6875
-1
8,034.6875
Vehicle A and Vehicle B start from points A and B, respectively, at the same time and travel towards each other. They meet after 3 hours, at which point Vehicle A turns back towards point A, and Vehicle B continues forward. After Vehicle A reaches point A, it turns around and heads towards point B. Half an hour later, ...
7.2
0
7,751.5
-1
7,751.5
Let \( N \) be the total number of students in the school before the New Year, among which \( M \) are boys, making up \( k \) percent of the total. This means \( M = \frac{k}{100} N \), or \( 100M = kN \). After the New Year, the number of boys became \( M+1 \), and the total number of students became \( N+3 \). If ...
197
0.375
7,701.875
7,044.666667
8,096.2
In right triangle $ABC$, $\sin A = \frac{3}{5}$ and $\sin B = 1$. Find $\sin C$.
\frac{4}{5}
1
2,102.5
2,102.5
-1
An isosceles trapezoid $A B C D$ with bases $A B$ and $C D$ has $A B=13, C D=17$, and height 3. Let $E$ be the intersection of $A C$ and $B D$. Circles $\Omega$ and $\omega$ are circumscribed about triangles $A B E$ and $C D E$. Compute the sum of the radii of $\Omega$ and $\omega$.
39
Let $\Omega$ have center $O$ and radius $R$ and let $\omega$ have center $P$ and radius $M$. Let $Q$ be the intersection of $A B$ and $O E$. Note that $O E$ is the perpendicular bisector of $A B$ because the trapezoid is isosceles. Also, we see $O E$ is the circumradius of $\Omega$. On the other hand, we know by simila...
0.375
7,926.6875
7,484.5
8,192
As shown in the diagram, in the square \(ABCD\), \(AB = 2\). Draw an arc with center \(C\) and radius equal to \(CD\), and another arc with center \(B\) and radius equal to \(BA\). The two arcs intersect at \(E\). What is the area of the sector \(BAE\)?
\frac{\pi}{3}
0.75
4,994.4375
4,464.333333
6,584.75
What is the correct ordering of the three numbers $\frac{5}{19}$, $\frac{7}{21}$, and $\frac{9}{23}$, in increasing order?
\frac{5}{19} < \frac{7}{21} < \frac{9}{23}
To find the correct ordering of the fractions $\frac{5}{19}$, $\frac{7}{21}$, and $\frac{9}{23}$, we can compare each pair of fractions. 1. **Simplify $\frac{7}{21}$:** \[\frac{7}{21} = \frac{1}{3}\] 2. **Compare $\frac{5}{19}$ and $\frac{7}{21}$:** To compare $\frac{5}{19}$ and $\frac{1}{3}$, we find a common ...
0.1875
5,439.625
4,989.666667
5,543.461538
Consider the case when all numbers are equal. $\frac{5}{4} n + \frac{5}{4} = n$. If the first number is -5, then all numbers will be equal to -5. The same applies to all cases where the first number is equal to $-5 + 1024n$, $n \in \mathbb{Z}$.
-5
0.0625
8,053.0625
8,061
8,052.533333
Evaluate \[i^{14762} + i^{14763} + i^{14764} + i^{14765}.\]
0
1
2,187.625
2,187.625
-1
Let \( x, y, z \) be complex numbers such that: \[ xy + 3y = -9, yz + 3z = -9, zx + 3x = -9. \] Determine all possible values of \( xyz \).
27
0.625
6,363.5
5,942.4
7,065.333333
What is $100(100-3)-(100 \cdot 100-3)$?
-297
We are given the expression \(100(100-3)-(100\cdot100-3)\) and need to simplify it. 1. **Distribute and simplify inside the parentheses:** \[ 100(100-3) = 100 \times 97 = 9700 \] Here, we calculate \(100 - 3 = 97\) and then multiply by 100. 2. **Simplify the second part of the expression:** \[ 100 \...
0.9375
389.625
386.466667
437
Given a positive geometric sequence $\{a_{n}\}$, if ${a_m}{a_n}=a_3^2$, find the minimum value of $\frac{2}{m}+\frac{1}{{2n}}$.
\frac{3}{4}
1
3,614.625
3,614.625
-1
A positive number is called $n$-primable if it is divisible by $n$ and each of its digits is a one-digit prime number. How many 3-primable positive integers are there that are less than 1000?
28
0.0625
8,119.1875
7,027
8,192
Three boys \( B_{1}, B_{2}, B_{3} \) and three girls \( G_{1}, G_{2}, G_{3} \) are to be seated in a row according to the following rules: 1) A boy will not sit next to another boy and a girl will not sit next to another girl, 2) Boy \( B_{1} \) must sit next to girl \( G_{1} \). If \( s \) is the number of different s...
40
0
7,889.8125
-1
7,889.8125
A large supermarket purchased a popular disinfectant laundry detergent. Due to the rise in raw material prices, the cost price per bottle of detergent this year increased by $4$ compared to last year. The quantity of detergent purchased for $1440$ yuan this year is the same as the quantity purchased for $1200$ yuan las...
8100
1
3,705.25
3,705.25
-1
What is the smallest positive integer $n$ for which $11n-8$ and $5n + 9$ share a common factor greater than $1$?
165
0
5,366.9375
-1
5,366.9375
Two lines with slopes $\frac{1}{2}$ and $2$ intersect at $(2,2)$. What is the area of the triangle enclosed by these two lines and the line $x+y=10$ ?
6
1. **Identify the equations of the lines**: - The line with slope $\frac{1}{2}$ passing through $(2,2)$ has the equation $y - 2 = \frac{1}{2}(x - 2)$, which simplifies to $y = \frac{1}{2}x + 1$. - The line with slope $2$ passing through $(2,2)$ has the equation $y - 2 = 2(x - 2)$, which simplifies to $y = 2x - 2...
1
3,591.75
3,591.75
-1
Given a sequence ${{a_{n}}}$ where all terms are non-zero, the sum of the first $n$ terms is ${{S_{n}}}$, and it satisfies ${{a_{1}}=a,}$ $2{{S_{n}}={{a_{n}}{{a_{n+1}}}}}$. (I) Find the value of ${{a_{2}}}$; (II) Find the general formula for the $n^{th}$ term of the sequence; (III) If $a=-9$, find the minimum value of...
-15
0.1875
7,794
6,069.333333
8,192
You have a whole pizza in the refrigerator. On your first trip to the refrigerator, you eat half the pizza. On each successive trip, you eat half of the remaining pizza. After five trips to the refrigerator, what fractional part of the pizza have you eaten?
\frac{31}{32}
1
2,466
2,466
-1
How many one-thirds are in one-sixth?
\frac{1}{2}
1
1,504.625
1,504.625
-1
Given an arithmetic sequence $\\{a_{n}\\}$, let $S_{n}$ denote the sum of its first $n$ terms. If $a_{4}=-12$ and $a_{8}=-4$: $(1)$ Find the general term formula for the sequence; $(2)$ Find the minimum value of $S_{n}$ and the corresponding value of $n$.
-90
0.3125
5,580.5
5,150.2
5,776.090909
If $x + x^2 + x^3 + \ldots + x^9 + x^{10} = a_0 + a_1(1 + x) + a_2(1 + x)^2 + \ldots + a_9(1 + x)^9 + a_{10}(1 + x)^{10}$, then $a_9 = \_\_\_\_\_\_\_\_$.
-9
0.4375
7,042.625
5,564.857143
8,192
Five packages are delivered to five houses, one to each house. If these packages are randomly delivered, what is the probability that exactly three of them are delivered to the correct houses? Express your answer as a common fraction.
\frac{1}{12}
1
3,494.8125
3,494.8125
-1
The graph of $y = f(x)$ is shown below. [asy] unitsize(0.5 cm); real func(real x) { real y; if (x >= -3 && x <= 0) {y = -2 - x;} if (x >= 0 && x <= 2) {y = sqrt(4 - (x - 2)^2) - 2;} if (x >= 2 && x <= 3) {y = 2*(x - 2);} return(y); } int i, n; for (i = -5; i <= 5; ++i) { draw((i,-5)--(i,5),gray(0.7)); ...
\text{E}
0
7,663.375
-1
7,663.375
Consider an infinite grid of unit squares. An $n$-omino is a subset of $n$ squares that is connected. Below are depicted examples of 8 -ominoes. Two $n$-ominoes are considered equivalent if one can be obtained from the other by translations and rotations. What is the number of distinct 15 -ominoes? Your score will be e...
3426576
We claim that there are approximately $\frac{3^{n-1}}{4} n$-ominoes. First, we define an order on the squares in an $n$-omino, as follows: we order the squares from left to right, and within a column, we order the squares from top to bottom. We construct an $n$-omino by starting with a single square and attaching squar...
0
5,151.0625
-1
5,151.0625
How many rational terms are in the expansion of a) $(\sqrt{2}+\sqrt[4]{3})^{100}$ b) $(\sqrt{2}+\sqrt[3]{3})^{300}$?
51
1
3,211.3125
3,211.3125
-1
There is a solid iron cone with a base radius of $3cm$ and a slant height of $5cm$. After melting it at high temperature and casting it into a solid iron sphere (without considering any loss), the radius of this iron sphere is _______ $cm$.
\sqrt[3]{9}
1
2,629.6875
2,629.6875
-1
Given $x, y \in (-1, 1)$, find the minimum value of the expression $$\sqrt {(x+1)^{2}+(y-1)^{2}}+\sqrt {(x+1)^{2}+(y+1)^{2}}+\sqrt {(x-1)^{2}+(y+1)^{2}}+\sqrt {(x-1)^{2}+(y-1)^{2}}.$$
4\sqrt{2}
0.5
7,035.0625
5,878.125
8,192
Let $P(x)=x^{3}+a x^{2}+b x+2015$ be a polynomial all of whose roots are integers. Given that $P(x) \geq 0$ for all $x \geq 0$, find the sum of all possible values of $P(-1)$.
9496
Since all the roots of $P(x)$ are integers, we can factor it as $P(x)=(x-r)(x-s)(x-t)$ for integers $r, s, t$. By Viete's formula, the product of the roots is $r s t=-2015$, so we need three integers to multiply to -2015. $P(x)$ cannot have two distinct positive roots $u, v$ since otherwise, $P(x)$ would be negative at...
0
7,300.25
-1
7,300.25
Find the number of pairs of natural numbers \((x, y)\) such that \(1 \leq x, y \leq 1000\) and \(x^2 + y^2\) is divisible by 5.
200000
0
7,119.625
-1
7,119.625
Let $\triangle PQR$ be a triangle in the plane, and let $S$ be a point outside the plane of $\triangle PQR$, so that $SPQR$ is a pyramid whose faces are all triangles. Suppose that every edge of $SPQR$ has length $18$ or $41$, but no face of $SPQR$ is equilateral. Then what is the surface area of $SPQR$?
1440
0.125
7,718
5,613
8,018.714286
The sum of the three largest natural divisors of a natural number \( N \) is 10 times the sum of its three smallest natural divisors. Find all possible values of \( N \).
40
0
8,192
-1
8,192
Consider finding the result when we compute the series $$1^3 + 2^3 + 3^3 + \dots + 49^3 + 50^3$$ and the series $$(-1)^3 + (-2)^3 + (-3)^3 + \dots + (-49)^3 + (-50)^3,$$ then subtract the second series' result from the first series' result. What is the sum?
3251250
1
2,803.8125
2,803.8125
-1
Given that $\tan α$ and $\tan β$ are the roots of the equation $x^{2}+3 \sqrt {3}x+4=0$, and $\(- \frac {π}{2} < α < \frac {π}{2}\)$, $\(- \frac {π}{2} < β < \frac {π}{2}\)$, find $α+β$.
- \frac {2\pi}{3}
0.375
6,319.4375
5,270.333333
6,948.9
What is the smallest integer larger than $(\sqrt{5}+\sqrt{3})^4$?
248
0.8125
5,788.1875
5,233.461538
8,192
A rectangular solid has three adjacent faces with areas of $1$, $2$, and $2$, respectively. All the vertices of the rectangular solid are located on the same sphere. Find the volume of this sphere.
\sqrt{6}\pi
0.875
3,621.5625
3,565
4,017.5
If the set $\{1, a, \frac{b}{a}\}$ equals $\{0, a^2, a + b\}$, find the value of $a - b$.
-1
0.25
6,922.875
6,766.75
6,974.916667
If $A=2+i$, $O=-4$, $P=-i$, and $S=2+4i$, find $A-O+P+S$.
8+4i
0.9375
2,545.4375
2,169
8,192
The positive integers from 1 to 576 are written in a 24 by 24 grid so that the first row contains the numbers 1 to 24, the second row contains the numbers 25 to 48, and so on. An 8 by 8 square is drawn around 64 of these numbers. The sum of the numbers in the four corners of the 8 by 8 square is 1646. What is the numbe...
499
0.625
5,734.625
4,483.1
7,820.5
A farmer buys 600 cows. He sells 500 of them for the price he paid for all 600 cows. The remaining 100 cows are sold for 10% more per cow than the price of the 500 cows. Calculate the percentage gain on the entire transaction.
22\%
1
2,424.9375
2,424.9375
-1
The expression $\log_{y^6}{x}\cdot\log_{x^5}{y^2}\cdot\log_{y^4}{x^3}\cdot\log_{x^3}{y^4}\cdot\log_{y^2}{x^5}$ can be written as $a\log_y{x}$ for what constant $a$?
\frac16
0.6875
5,110.0625
3,709.181818
8,192
Find all integers $n \geq 3$ such that among any $n$ positive real numbers $a_1, a_2, \hdots, a_n$ with $\text{max}(a_1,a_2,\hdots,a_n) \leq n \cdot \text{min}(a_1,a_2,\hdots,a_n)$, there exist three that are the side lengths of an acute triangle.
n \geq 13
To solve this problem, we need to determine for which integers \( n \geq 3 \), any set of \( n \) positive real numbers \( a_1, a_2, \ldots, a_n \), under the condition \( \max(a_1, a_2, \ldots, a_n) \leq n \cdot \min(a_1, a_2, \ldots, a_n) \), contains three numbers that can serve as the side lengths of an acute tria...
0
8,192
-1
8,192
Let $s$ be the limiting sum of the geometric series $4 - \frac{8}{3} + \frac{16}{9} - \dots$, as the number of terms increases without bound. Then $s$ equals:
2.4
1. **Identify the first term and common ratio**: The given series is $4 - \frac{8}{3} + \frac{16}{9} - \dots$. The first term $a$ is clearly $4$. To find the common ratio $r$, we observe the ratio between successive terms: \[ r = \frac{-\frac{8}{3}}{4} = -\frac{2}{3} \] and \[ \frac{\frac{16}{9}}{...
0
3,580.375
-1
3,580.375
The sales tax rate in Rubenenkoville is 6%. During a sale at the Bergville Coat Closet, the price of a coat is discounted 20% from its $90.00 price. Two clerks, Jack and Jill, calculate the bill independently. Jack rings up $90.00 and adds 6% sales tax, then subtracts 20% from this total. Jill rings up $90.00, subtract...
$0
1. **Calculate Jack's total:** - Jack first calculates the total price including tax on the original price: \[ 90.00 \times 1.06 = 95.40 \text{ dollars} \] - Then, he applies the 20% discount to this total: \[ 95.40 \times 0.80 = 76.32 \text{ dollars} \] 2. **Calculate Jill's total:...
0
3,621.25
-1
3,621.25
For any real number \( x \), let \( f(x) \) be the minimum of the values \( 4x + 1 \), \( x + 2 \), and \( -2x + 4 \). What is the maximum value of \( f(x) \)?
\frac{8}{3}
0.6875
6,748.75
6,092.727273
8,192
For which maximal $N$ there exists an $N$-digit number with the following property: among any sequence of its consecutive decimal digits some digit is present once only? Alexey Glebov
1023
To determine for which maximal \( N \) there exists an \( N \)-digit number satisfying the given property, we need to find an \( N \)-digit number such that in every sequence of consecutive decimal digits, there is at least one digit that appears only once. Let's explore the conditions and find the appropriate \( N \)...
0
7,947.5
-1
7,947.5
In the diagram, \(PQRS\) is a rectangle with \(SR = 15\). Point \(T\) is above \(PS\) and point \(U\) is on \(PS\) so that \(TU\) is perpendicular to \(PS\). If \(PT = 10\) and \(US = 4\) and the area of \(PQRS\) is 180, what is the area of \(\triangle PTS\)?
36
0.4375
5,082.5625
3,566
6,262.111111
If $|x-\log y|=x+\log y$ where $x$ and $\log y$ are real, then
x(y-1)=0
Given the equation $|x-\log y|=x+\log y$, we need to consider the properties of the absolute value function and the possible values of $x$ and $\log y$. 1. **Understanding the absolute value equation**: The absolute value equation $|a| = b$ holds if and only if $a = b$ or $a = -b$, and $b \geq 0$. Applying this to ...
0
4,643.9375
-1
4,643.9375
Given a sequence $\{a_{n}\}$ that satisfies ${a}_{n+1}=\frac{1}{3}{a}_{n}$, if $a_{4}+a_{5}=4$, calculate $a_{2}+a_{3}$.
36
0.75
4,416.3125
3,157.75
8,192
Given a geometric sequence $\{a_n\}$ satisfies $a_2a_5=2a_3$, and $a_4$, $\frac{5}{4}$, $2a_7$ form an arithmetic sequence, the maximum value of $a_1a_2a_3…a_n$ is \_\_\_\_\_\_.
1024
0.9375
4,538.125
4,568.466667
4,083
Three triangles. Inside triangle $ABC$, a random point $M$ is chosen. What is the probability that the area of one of the triangles $ABM$, $BCM$, or $CAM$ will be greater than the sum of the areas of the other two?
0.75
0
7,951.1875
-1
7,951.1875
(1) Simplify: $f(α)= \dfrac {\sin (α+ \dfrac {3}{2}π)\sin (-α+π)\cos (α+ \dfrac {π}{2})}{\cos (-α -π )\cos (α - \dfrac {π}{2})\tan (α +π )}$ (2) Evaluate: $\tan 675^{\circ}+\sin (-330^{\circ})+\cos 960^{\circ}$
-1
1
3,935.375
3,935.375
-1
If $y = -x^2 + 5$ and $x$ is a real number, then what is the maximum value possible for $y$?
5
1
1,324.0625
1,324.0625
-1
Observe: $$ \begin{array}{l} 1 \times 2 \times 3 \times 4 + 1 = 5^{2} \\ 2 \times 3 \times 4 \times 5 + 1 = 11^{2} \\ 3 \times 4 \times 5 \times 6 + 1 = 19^{2} \\ \ldots \ldots \end{array} $$ Calculate $\sqrt{2020 \times 2021 \times 2022 \times 2023 + 1}=$
4086461
1
3,171.9375
3,171.9375
-1
The noon temperatures for seven consecutive days were $80^{\circ}$, $79^{\circ}$, $81^{\circ}$, $85^{\circ}$, $87^{\circ}$, $89^{\circ}$, and $87^{\circ}$ Fahrenheit. What is the mean noon temperature, in degrees Fahrenheit, for the week?
84
0.9375
1,280.375
1,348.533333
258
In the final stage of a professional bowling competition, the top five players compete as follows: - The fifth place player competes against the fourth place player. - The loser of the match receives the 5th place award. - The winner then competes against the third place player. - The loser of this match receives the...
16
0.25
7,677.0625
6,132.25
8,192
$A B C$ is a triangle with points $E, F$ on sides $A C, A B$, respectively. Suppose that $B E, C F$ intersect at $X$. It is given that $A F / F B=(A E / E C)^{2}$ and that $X$ is the midpoint of $B E$. Find the ratio $C X / X F$.
\sqrt{5}
Let $x=A E / E C$. By Menelaus's theorem applied to triangle $A B E$ and line $C X F$, $$1=\frac{A F}{F B} \cdot \frac{B X}{X E} \cdot \frac{E C}{C A}=\frac{x^{2}}{x+1}$$ Thus, $x^{2}=x+1$, and $x$ must be positive, so $x=(1+\sqrt{5}) / 2$. Now apply Menelaus to triangle $A C F$ and line $B X E$, obtaining $$1=\frac{A ...
0.3125
7,671.125
6,525.2
8,192
Given $|x|=4$, $|y|=2$, and $x<y$, then the value of $x\div y$ is ______.
-2
0.625
722.5
691.3
774.5
Let \( f(x) = x^2 + px + q \). It is known that the inequality \( |f(x)| > \frac{1}{2} \) has no solutions on the interval \([1, 3]\). Find \( \underbrace{f(f(\ldots f}_{2017}\left(\frac{3+\sqrt{7}}{2}\right)) \ldots) \). If necessary, round your answer to two decimal places.
0.18
0.0625
8,187.4375
8,119
8,192
A quadrilateral is inscribed in a circle of radius $200\sqrt{2}$. Three of the sides of this quadrilateral have length $200$. What is the length of the fourth side?
500
1. **Setup and Diagram**: Let quadrilateral $ABCD$ be inscribed in a circle $O$ with radius $200\sqrt{2}$. Assume $AD$ is the side of unknown length, and $AB = BC = CD = 200$. Draw radii $OA$, $OB$, $OC$, and $OD$. 2. **Using the Pythagorean Theorem in $\triangle BOC$**: Draw altitude $OH$ from $O$ to side $BC$ at poi...
0.625
6,526.8125
5,527.7
8,192
Lydia likes a five-digit number if none of its digits are divisible by 3. Find the total sum of the digits of all five-digit numbers that Lydia likes.
174960
0.5
5,501.5
4,711.75
6,291.25
What is the smallest positive value of $m$ so that the equation $10x^2 - mx + 360 = 0$ has integral solutions with one root being a multiple of the other?
120
0.625
6,803.4375
5,970.3
8,192
A cryptographer designed the following method to encode natural numbers: first, represent the natural number in base 5, then map the digits in the base 5 representation to the elements of the set $\{V, W, X, Y, Z\}$ in a one-to-one correspondence. Using this correspondence, he found that three consecutive increasing na...
108
0.375
7,141.125
6,073.5
7,781.7
Triangle $\triangle DEF$ has a right angle at $F$, $\angle D = 60^\circ$, and $DF=12$. Find the radius of the incircle of $\triangle DEF$.
6(\sqrt{3}-1)
0.3125
4,883
4,109
5,234.818182
In the rectangular coordinate system $xOy$, the equation of line $C_1$ is $y=-\sqrt{3}x$, and the parametric equations of curve $C_2$ are given by $\begin{cases}x=-\sqrt{3}+\cos\varphi\\y=-2+\sin\varphi\end{cases}$. Establish a polar coordinate system with the coordinate origin as the pole and the positive half of the ...
\sqrt{3}
0.125
8,146.0625
7,824.5
8,192
A basketball player scored 18, 22, 15, and 20 points respectively in her first four games of a season. Her points-per-game average was higher after eight games than it was after these four games. If her average after nine games was greater than 19, determine the least number of points she could have scored in the ninth...
21
0.5625
5,725.5625
4,083
7,837.428571
When one ounce of water is added to a mixture of acid and water, the new mixture is $20\%$ acid. When one ounce of acid is added to the new mixture, the result is $33\frac13\%$ acid. The percentage of acid in the original mixture is
25\%
1. **Define Variables:** Let $a$ be the original number of ounces of acid and $w$ be the original number of ounces of water in the mixture. 2. **Set Up Equations:** - After adding one ounce of water, the mixture becomes $20\%$ acid. Therefore, the equation is: \[ \frac{a}{a + w + 1} = \frac{1}{5} ...
1
2,491.9375
2,491.9375
-1
How can 13 rectangles of sizes $1 \times 1, 2 \times 1, 3 \times 1, \ldots, 13 \times 1$ be combined to form a rectangle, where all sides are greater than 1?
13 \times 7
0
7,998.125
-1
7,998.125
Define a $\it{good\ word}$ as a sequence of letters that consists only of the letters A, B, C, and D — some of these letters may not appear in the sequence — where A is never immediately followed by B or D, B is never immediately followed by C, C is never immediately followed by A, and D is never immediately followed b...
512
0.125
7,477.5
7,154
7,523.714286