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Find the least common multiple of 24 and 90.
360
1
2,419.625
2,419.625
-1
$x$, $y$ and $z$ are positive reals such that $x+y+z=xyz$. Find the minimum value of: \[ x^7(yz-1)+y^7(zx-1)+z^7(xy-1) \]
162\sqrt{3}
Given that \( x \), \( y \), and \( z \) are positive reals such that \( x + y + z = xyz \), we aim to find the minimum value of: \[ x^7(yz-1) + y^7(zx-1) + z^7(xy-1). \] First, we use the given condition \( x + y + z = xyz \). By the AM-GM inequality, we have: \[ xyz = x + y + z \geq 3\sqrt[3]{xyz}, \] which implies...
0.125
7,962.25
6,861
8,119.571429
If $a=\log_8 225$ and $b=\log_2 15$, then
$a=2b/3$
1. **Express $a$ and $b$ in terms of logarithms with a common base:** Given $a = \log_8 225$ and $b = \log_2 15$, we can use the change of base formula to express both logarithms in terms of base $2$: \[ a = \log_8 225 = \frac{\log_2 225}{\log_2 8} \] \[ b = \log_2 15 \] Note that $\log_2 8 = 3$...
0
3,001.9375
-1
3,001.9375
A box contains a collection of triangular, square, and rectangular tiles. There are 32 tiles in the box, consisting of 114 edges in total. Each rectangle has 5 edges due to a small notch cut on one side. Determine the number of square tiles in the box.
10
0
8,074.5
-1
8,074.5
There are 5 integers written on the board. The sums of these integers taken in pairs resulted in the following set of 10 numbers: $6, 9, 10, 13, 13, 14, 17, 17, 20, 21$. Determine which numbers are written on the board. Provide their product as the answer.
4320
0.875
4,071.8125
3,483.214286
8,192
If \( n = 7 \), which of the following expressions is equal to an even integer: \( 9n, n+8, n^2, n(n-2), 8n \)?
8n
When \( n=7 \), we have \( 9n=63, n+8=15, n^2=49, n(n-2)=35, 8n=56 \). Therefore, \( 8n \) is even. For every integer \( n \), the expression \( 8n \) is equal to an even integer.
0.9375
1,595.4375
1,593.066667
1,631
A basketball team consists of 18 players, including a set of 3 triplets: Bob, Bill, and Ben; and a set of twins: Tim and Tom. In how many ways can we choose 7 starters if exactly two of the triplets and one of the twins must be in the starting lineup?
4290
0.9375
3,119.5625
2,793.066667
8,017
Find all functions $f:\mathbb{R}\rightarrow\mathbb{R}$ that satisfy \[f(x^2-y)+2yf(x)=f(f(x))+f(y)\] for all $x,y\in\mathbb{R}$ .
\[ f(x) = -x^2, \quad f(x) = 0, \quad f(x) = x^2 \]
Plugging in $y$ as $0:$ \begin{equation} f(x^2)=f(f(x))+f(0) \text{ } (1) \end{equation} Plugging in $x, y$ as $0:$ \[f(0)=f(f(0))+f(0)\] or \[f(f(0))=0\] Plugging in $x$ as $0:$ \[f(-y)+2yf(0)=f(f(0))+f(y),\] but since $f(f(0))=0,$ \begin{equation} f(-y)+2yf(0)=f(y) \text{ } (2) \end{equation} Plugging in $y^2$ inst...
0
8,090.25
-1
8,090.25
Find the maximum value of the function \( f(x) \), which is defined as the minimum of the three functions \( 4x + 1 \), \( x + 2 \), and \( -2x + 4 \) for each real number \( x \).
\frac{8}{3}
0.875
6,096.9375
5,944.928571
7,161
For a complex number $z \neq 3$ , $4$ , let $F(z)$ denote the real part of $\tfrac{1}{(3-z)(4-z)}$ . If \[ \int_0^1 F \left( \frac{\cos 2 \pi t + i \sin 2 \pi t}{5} \right) \; dt = \frac mn \] for relatively prime positive integers $m$ and $n$ , find $100m+n$ . *Proposed by Evan Chen*
100
0
7,892.625
-1
7,892.625
Evaluate $\log_432$.
\frac{5}{2}
0.9375
2,517.625
2,139.333333
8,192
The total \( T \) is obtained as the sum of the integers from 2006 to 2036 inclusive. What is the sum of all the prime factors of \( T \)?
121
0.875
3,428.5625
3,508.142857
2,871.5
Let the coefficient of \( x^{1992} \) in the power series \( (1 + x)^{\alpha} = 1 + \alpha x + \dots \) be \( C(\alpha) \). Find \( \int_{0}^{1} C(-y-1) \sum_{k=1}^{1992} \frac{1}{y+k} \, dy \).
1992
0.125
7,457.5625
4,161
7,928.5
Let $a$ and $b$ be real numbers bigger than $1$ . Find maximal value of $c \in \mathbb{R}$ such that $$ \frac{1}{3+\log _{a} b}+\frac{1}{3+\log _{b} a} \geq c $$
\frac{1}{3}
0.5625
6,485.1875
5,992.888889
7,118.142857
Let \( ABCD \) be a square with side length 1. Points \( X \) and \( Y \) are on sides \( BC \) and \( CD \) respectively such that the areas of triangles \( ABX \), \( XCY \), and \( YDA \) are equal. Find the ratio of the area of \( \triangle AXY \) to the area of \( \triangle XCY \).
\sqrt{5}
0.625
6,788.3125
6,198.4
7,771.5
In $\triangle ABC$, the sides opposite to the internal angles $A$, $B$, and $C$ are $a$, $b$, and $c$ respectively. Given that $a^{2}+c^{2}-b^{2}=ac$, $c=2$, and point $G$ satisfies $| \overrightarrow{BG}|= \frac { \sqrt {19}}{3}$ and $\overrightarrow{BG}= \frac {1}{3}( \overrightarrow{BA}+ \overrightarrow{BC})$, find ...
\frac {3 \sqrt {21}}{14}
0
7,366.625
-1
7,366.625
Seven thousand twenty-two can be written as
7022
0.375
293.75
269.166667
308.5
Let $N$ be the number of positive integers that are less than or equal to $5000$ and whose base-$3$ representation has more $1$'s than any other digit. Find the remainder when $N$ is divided by $1000$.
379
0
8,192
-1
8,192
Let $ABCD$ be an isosceles trapezoid with $\overline{BC} \parallel \overline{AD}$ and $AB=CD$. Points $X$ and $Y$ lie on diagonal $\overline{AC}$ with $X$ between $A$ and $Y$. Suppose $\angle AXD = \angle BYC = 90^\circ$, $AX = 3$, $XY = 1$, and $YC = 2$. What is the area of $ABCD?$
$3\sqrt{35}$
1. **Setting up the coordinate system**: Place $X$ at the origin $(0,0)$, align $AC$ along the $x$-axis, and $DX$ along the $y$-axis. This gives us: - $X = (0,0)$ - $A = (3,0)$ (since $AX = 3$) - $Y = (-1,0)$ (since $XY = 1$) - $C = (-3,0)$ (since $YC = 2$) 2. **Locating points $B$ and $D$**: Let $BY = u$ ...
0
7,354.0625
-1
7,354.0625
A geometric sequence $(a_n)$ has $a_1=\sin x$, $a_2=\cos x$, and $a_3= \tan x$ for some real number $x$. For what value of $n$ does $a_n=1+\cos x$?
8
1. **Identify the common ratio**: Given a geometric sequence $(a_n)$ with $a_1 = \sin x$, $a_2 = \cos x$, and $a_3 = \tan x$, we know that the common ratio $r$ satisfies $a_2 = r a_1$ and $a_3 = r a_2$. Thus, we have: \[ \cos x = r \sin x \quad \text{and} \quad \tan x = r \cos x \] Solving for $r$ from the ...
0.3125
7,644.875
7,190.4
7,851.454545
Eight distinct integers are picked at random from $\{1,2,3,\ldots,15\}$. What is the probability that, among those selected, the third smallest is $5$?
\frac{72}{307}
0
4,001.4375
-1
4,001.4375
Compute the definite integral: $$ \int_{0}^{\pi} 2^{4} \cdot \sin ^{6}\left(\frac{x}{2}\right) \cos ^{2}\left(\frac{x}{2}\right) d x $$
\frac{5\pi}{8}
0.5625
6,698.6875
5,537.222222
8,192
Find the smallest positive integer $k$ such that $z^{10}+z^{9}+z^{6}+z^{5}+z^{4}+z+1$ divides $z^{k}-1$.
84
Let $Q(z)$ denote the polynomial divisor. We need that the roots of $Q$ are $k$-th roots of unity. With this in mind, we might observe that solutions to $z^{7}=1$ and $z \neq 1$ are roots of $Q$, which leads to its factorization. Alternatively, we note that $$(z-1) Q(z)=z^{11}-z^{9}+z^{7}-z^{4}+z^{2}-1=\left(z^{4}-z^{2...
0
7,579.5
-1
7,579.5
How many possible distinct arrangements are there of the letters in the word SUCCESS?
420
0.125
2,972.125
1,733
3,149.142857
On a mathematics quiz, there were $6x$ problems. Lucky Lacy missed $2x$ of them. What percent of the problems did she get correct?
66.67\%
0
3,376.1875
-1
3,376.1875
Find all functions $f: \mathbb{R}^+ \to \mathbb{R}^+$ such that $$(z + 1)f(x + y) = f(xf(z) + y) + f(yf(z) + x),$$ for all positive real numbers $x, y, z$.
f(x) = x
To solve this functional equation problem, we want to find all functions \( f: \mathbb{R}^+ \to \mathbb{R}^+ \) such that: \[ (z + 1)f(x + y) = f(xf(z) + y) + f(yf(z) + x) \] for all positive real numbers \(x, y, z\). Our goal is to prove that the function satisfies \( f(x) = x \). First, let's investigate the cond...
0.125
8,133.75
7,726
8,192
In an opaque bag, there are $10$ balls each of red, white, and yellow colors, all identical except for the color. At least how many balls must be drawn to ensure that two balls of different colors are drawn? At least how many balls must be drawn to ensure that two yellow balls are drawn?
22
0.0625
6,842.625
7,374
6,807.2
Given that Connie adds $3$ to a number and gets $45$ as her answer, but she should have subtracted $3$ from the number to get the correct answer, determine the correct number.
39
0.9375
2,005.9375
1,593.533333
8,192
The first term of a sequence is $2005$. Each succeeding term is the sum of the cubes of the digits of the previous term. What is the ${2005}^{\text{th}}$ term of the sequence?
250
0.75
5,900.375
5,136.5
8,192
Write the expression $\frac{4+3c}{7}+2$ as a single fraction.
\frac{18+3c}{7}
0
1,592.6875
-1
1,592.6875
In the ancient Chinese mathematical text "The Mathematical Classic of Sunzi", there is a problem stated as follows: "Today, a hundred deer enter the city. Each family takes one deer, but not all are taken. Then, three families together take one deer, and all deer are taken. The question is: how many families are there ...
75
0.25
7,350.4375
5,765
7,878.916667
Five runners, $P$, $Q$, $R$, $S$, $T$, have a race, and $P$ beats $Q$, $P$ beats $R$, $Q$ beats $S$, and $T$ finishes after $P$ and before $Q$. Who could NOT have finished third in the race?
P and S
1. **Analyze the given information**: We know that $P$ beats $Q$, $P$ beats $R$, $Q$ beats $S$, and $T$ finishes after $P$ but before $Q$. 2. **Determine the possible positions for $P$**: - Since $P$ beats $Q$, $R$, and $S$ (by transitivity from $Q$ beating $S$), $P$ must be in the first position. This eliminates $...
0
7,832.625
-1
7,832.625
There is a round table with 9 chairs, and 4 people are seated randomly. What is the probability that no two people are sitting next to each other?
1/14
0.4375
7,616.125
6,939.142857
8,142.666667
In $\triangle ABC$, the sides opposite to angles $A$, $B$, $C$ are $a$, $b$, $c$ respectively. Angles $A$, $B$, $C$ form an arithmetic sequence, $c - a = 1$, and $b = \sqrt{7}$. (I) Find the area $S$ of $\triangle ABC$. (II) Find the value of $\sin\left(2C + \frac{\pi}{4}\right)$.
\frac{3\sqrt{6} - 13\sqrt{2}}{28}
0
6,759.625
-1
6,759.625
What is $\frac{3}{4}$ divided by $\frac{7}{8}$?
\frac{6}{7}
1
2,427.375
2,427.375
-1
$\sqrt{3+2\sqrt{2}}-\sqrt{3-2\sqrt{2}}$ is equal to
2
We are given the expression $\sqrt{3+2\sqrt{2}}-\sqrt{3-2\sqrt{2}}$ and need to find its value among the choices provided. 1. **Square the expression** to simplify: \[ \left(\sqrt{3+2\sqrt{2}} - \sqrt{3-2\sqrt{2}}\right)^2 = (\sqrt{3+2\sqrt{2}})^2 - 2\sqrt{3+2\sqrt{2}}\sqrt{3-2\sqrt{2}} + (\sqrt{3-2\sqrt{2}})^2 ...
1
2,049.9375
2,049.9375
-1
A group of cows and horses are randomly divided into two equal rows. Each animal in one row is directly opposite an animal in the other row. If 75 of the animals are horses and the number of cows opposite cows is 10 more than the number of horses opposite horses, determine the total number of animals in the group.
170
0.125
6,763.4375
3,874.5
7,176.142857
What is the least positive integer $m$ such that the following is true? *Given $\it m$ integers between $\it1$ and $\it{2023},$ inclusive, there must exist two of them $\it a, b$ such that $1 < \frac ab \le 2.$*
12
0.375
7,343.8125
6,062.833333
8,112.4
In a toy store, there are large and small plush kangaroos. In total, there are 100 of them. Some of the large kangaroos are female kangaroos with pouches. Each female kangaroo has three small kangaroos in her pouch, and the other kangaroos have empty pouches. Find out how many large kangaroos are in the store, given th...
31
0.1875
7,345.0625
5,446
7,783.307692
Given a cube of side length $8$ and balls of clay of radius $1.5$, determine the maximum number of balls that can completely fit inside the cube when the balls are reshaped but not compressed.
36
0.6875
6,924.625
6,348.545455
8,192
The sequence \(\{a_n\}\) is a geometric sequence with a common ratio of \(q\), where \(|q| > 1\). Let \(b_n = a_n + 1 (n \in \mathbb{N}^*)\), if \(\{b_n\}\) has four consecutive terms in the set \(\{-53, -23, 19, 37, 82\}\), find the value of \(q\).
-\dfrac{3}{2}
0
8,192
-1
8,192
Of all positive integers between 10 and 100, what is the sum of the non-palindrome integers that take exactly eight steps to become palindromes?
187
0
8,192
-1
8,192
Find the number of digits in the decimal representation of $2^{41}$.
13
Noticing that $2^{10}=1024 \approx 1000$ allows for a good estimate. Alternatively, the number of decimal digits of $n$ is given by $\left\lfloor\log _{10}(n)\right\rfloor+1$. Using $\log _{10}(2) \approx 0.31$ also gives the correct answer. The exact value of $2^{41}$ is 2199023255552.
0.875
4,961.75
4,500.285714
8,192
Compute \[ \left( 1 + \sin \frac {\pi}{12} \right) \left( 1 + \sin \frac {5\pi}{12} \right) \left( 1 + \sin \frac {7\pi}{12} \right) \left( 1 + \sin \frac {11\pi}{12} \right). \]
\frac{1}{16}
0
7,488.6875
-1
7,488.6875
Given that in the rectangular coordinate system $(xOy)$, the origin is the pole and the positive semi-axis of $x$ is the polar axis to establish a polar coordinate system, the polar coordinate equation of the conic section $(C)$ is $p^{2}= \frac {12}{3+\sin ^{2}\theta }$, the fixed point $A(0,- \sqrt {3})$, $F\_{1}$, $...
\frac {12}{5}
1
5,008.75
5,008.75
-1
The greatest common divisor of two integers is $(x+2)$ and their least common multiple is $x(x+2)$, where $x$ is a positive integer. If one of the integers is 24, what is the smallest possible value of the other one?
6
0.75
5,818.75
5,027.666667
8,192
Consider the sum \[ S_n = \sum_{k = 1}^n \frac{1}{\sqrt{2k-1}} \, . \] Determine $\lfloor S_{4901} \rfloor$ . Recall that if $x$ is a real number, then $\lfloor x \rfloor$ (the *floor* of $x$ ) is the greatest integer that is less than or equal to $x$ .
98
0.1875
8,077.5625
7,581.666667
8,192
Given the planar vectors $\overrightarrow {a}$ and $\overrightarrow {b}$, where $\overrightarrow {a}$ = (2cosα, 2sinα) and $\overrightarrow {b}$ = (cosβ, sinβ), if the minimum value of $|\overrightarrow {a} - λ\overrightarrow {b}|$ for any positive real number λ is $\sqrt{3}$, calculate $|\overrightarrow {a} - \overrig...
\sqrt{3}
0.75
5,761.625
4,951.5
8,192
$ABCD$ is a regular tetrahedron (right triangular pyramid). If $M$ is the midpoint of $\overline{CD}$, then what is $\cos \angle AMB$?
\frac{1}{3}
0.875
5,120.75
4,682
8,192
Jane Doe invested some amount of money into a savings account and mutual funds. The total amount she invested was \$320,000. If she invested 6 times as much in mutual funds as she did in the savings account, what was her total investment in mutual funds?
274,285.74
0
2,764
-1
2,764
Alice and the Cheshire Cat play a game. At each step, Alice either (1) gives the cat a penny, which causes the cat to change the number of (magic) beans that Alice has from $n$ to $5n$ or (2) gives the cat a nickel, which causes the cat to give Alice another bean. Alice wins (and the cat disappears) as soon as the numb...
35
Consider the number of beans Alice has in base 5. Note that $2008=31013_{5}, 42=132_{5}$, and $100=400_{5}$. Now, suppose Alice has $d_{k} \cdots d_{2} d_{1}$ beans when she wins; the conditions for winning mean that these digits must satisfy $d_{2} d_{1}=32, d_{k} \cdots d_{3} \geq 310$, and $d_{k} \cdots d_{3}=4i+1$ ...
0
8,192
-1
8,192
What is the sum of all the even integers between $200$ and $400$?
30300
0.0625
5,738.5
7,693
5,608.2
Given that there are 10 streetlights numbered from 1 to 10, two of which will be turned off under the conditions that two adjacent lights cannot be turned off at the same time and the lights at both ends cannot be turned off either, calculate the number of ways to turn off the lights.
21
0.5
6,827.25
5,705.375
7,949.125
Star lists the whole numbers $1$ through $30$ once. Emilio copies Star's numbers, replacing each occurrence of the digit $2$ by the digit $1$. Star adds her numbers and Emilio adds his numbers. How much larger is Star's sum than Emilio's?
103
1. **Identify the numbers affected by the digit change**: Star lists numbers from $1$ to $30$. Emilio replaces each occurrence of the digit $2$ with the digit $1$. We need to identify where the digit $2$ appears in these numbers. 2. **Count occurrences of the digit $2$**: - **As a tens digit**: The numbers $20$ thr...
0.0625
8,104.5
6,792
8,192
What is the sum of all the integers between -25.4 and 15.8, excluding the integer zero?
-200
0
5,040.25
-1
5,040.25
At a particular school with 43 students, each student takes chemistry, biology, or both. The chemistry class is three times as large as the biology class, and 5 students are taking both classes. How many people are in the chemistry class?
36
1
1,392.9375
1,392.9375
-1
Dave rolls a fair six-sided die until a six appears for the first time. Independently, Linda rolls a fair six-sided die until a six appears for the first time. Let $m$ and $n$ be relatively prime positive integers such that $\dfrac mn$ is the probability that the number of times Dave rolls his die is equal to or within...
41
Let $p$ be the probability that the number of times Dave rolls his die is equal to or within one of the number of times Linda rolls her die. (We will call this event "a win", and the opposite event will be "a loss".) Let both players roll their first die. With probability $\frac 1{36}$, both throw a six and we win. ...
0.1875
7,014.8125
4,068
7,694.846154
Suppose that $(a_{1}, \ldots, a_{20})$ and $(b_{1}, \ldots, b_{20})$ are two sequences of integers such that the sequence $(a_{1}, \ldots, a_{20}, b_{1}, \ldots, b_{20})$ contains each of the numbers $1, \ldots, 40$ exactly once. What is the maximum possible value of the sum $\sum_{i=1}^{20} \sum_{j=1}^{20} \min (a_{i}...
5530
Let $x_{k}$, for $1 \leq k \leq 40$, be the number of integers $i$ with $1 \leq i \leq 20$ such that $a_{i} \geq k$. Let $y_{k}$, for $1 \leq k \leq 40$, be the number of integers $j$ with $1 \leq j \leq 20$ such that $b_{j} \geq k$. It follows from the problem statement that $x_{k}+y_{k}$ is the number of elements of ...
0
8,192
-1
8,192
The number of trees in a park must be more than 80 and fewer than 150. The number of trees is 2 more than a multiple of 4, 3 more than a multiple of 5, and 4 more than a multiple of 6. How many trees are in the park?
98
0
3,819.8125
-1
3,819.8125
Nine barrels. In how many ways can nine barrels be arranged in three tiers so that the numbers written on the barrels that are to the right of any barrel or below it are larger than the number written on the barrel itself? An example of a correct arrangement is having 123 in the top row, 456 in the middle row, and 789 ...
42
0.25
6,900.25
4,836.25
7,588.25
In $\triangle ABC$, the sides opposite to angles $A$, $B$, and $C$ are $a$, $b$, and $c$ respectively. The function $f(x) = 2\cos x \sin (x - A) (x \in \mathbb{R})$ reaches its minimum value at $x = \frac{11\pi}{12}$. 1. Find the measure of angle $A$. 2. If $a = 7$ and $\sin B + \sin C = \frac{13\sqrt{3}}{14}$, find th...
10\sqrt{3}
0.75
5,629.6875
4,914.416667
7,775.5
A circle with area $A_1$ is contained in the interior of a larger circle with area $A_1+A_2$. If the radius of the larger circle is $3$, and if $A_1 , A_2, A_1 + A_2$ is an arithmetic progression, then the radius of the smaller circle is
\sqrt{3}
1. **Identify the areas of the circles**: Given that the area of the larger circle is $A_1 + A_2$ and its radius is $3$, we can calculate its area using the formula for the area of a circle, $A = \pi r^2$. Thus, the area of the larger circle is: \[ A_1 + A_2 = \pi \times 3^2 = 9\pi \] 2. **Arithmetic prog...
1
1,492.875
1,492.875
-1
The fifth grade has 120 teachers and students going to visit the Natural History Museum. A transportation company offers two types of vehicles to choose from: (1) A bus with a capacity of 40 people, with a ticket price of 5 yuan per person. If the bus is full, the ticket price can be discounted by 20%. (2) A minivan wi...
480
0.0625
4,391.1875
5,087
4,344.8
The graph of the function $f(x)=\sin (\omega x+\frac{π}{3})$ ($\omega\ \ \gt 0$) is shifted to the left by $\frac{π}{2}$ units to obtain the curve $C$. If $C$ is symmetric about the $y$-axis, then find the minimum value of $\omega$.
\frac{1}{3}
0.8125
5,416.4375
4,775.923077
8,192
Given the function $f(\cos x) = -f'(\frac{1}{2})\cos x + \sqrt{3}\sin^2 x$, find the value of $f(\frac{1}{2})$.
\sqrt{3}
0.875
4,554.375
4,358.785714
5,923.5
Convert $2014_{10}$ to base 9.
2677_9
1
2,197.625
2,197.625
-1
Let \( f(x) = 12x + 5 \). Find the sum of all \( x \) that satisfy the equation \( f^{-1}(x) = f((3x)^{-1}) \).
65
1
2,946.0625
2,946.0625
-1
What is the perimeter of pentagon $ABCDE$ in this diagram? [asy] pair cis(real r,real t) { return (r*cos(t),r*sin(t)); } pair a=(0,0); pair b=cis(1,-pi/2); pair c=cis(sqrt(2),-pi/4); pair d=cis(sqrt(3),-pi/4+atan(1/sqrt(2))); pair e=cis(2,-pi/4+atan(1/sqrt(2))+atan(1/sqrt(3))); dot(a); dot(b); dot(c); dot(d); dot(e); d...
6
0.125
7,261.375
6,058.5
7,433.214286
Describe how to place the vertices of a triangle in the faces of a cube in such a way that the shortest side of the triangle is the biggest possible.
\sqrt{2}
0.3125
7,430.25
5,827.2
8,158.909091
I have fifteen books, of which I want to bring two to read on vacation. However, out of these, there are three specific books that cannot be paired together (let's say they are volumes of the same series). How many different pairs can I choose?
102
0.625
1,201.0625
869.5
1,753.666667
The quadratic $ax^2 + bx + c$ can be expressed in the form $2(x - 4)^2 + 8$. When the quadratic $3ax^2 + 3bx + 3c$ is expressed in the form $n(x - h)^2 + k$, what is $h$?
4
1
2,366.6875
2,366.6875
-1
A set $\mathcal{S}$ of distinct positive integers has the following property: for every integer $x$ in $\mathcal{S},$ the arithmetic mean of the set of values obtained by deleting $x$ from $\mathcal{S}$ is an integer. Given that 1 belongs to $\mathcal{S}$ and that 2002 is the largest element of $\mathcal{S},$ what is t...
30
Let the sum of the integers in $\mathcal{S}$ be $N$, and let the size of $|\mathcal{S}|$ be $n+1$. After any element $x$ is removed, we are given that $n|N-x$, so $x\equiv N\pmod{n}$. Since $1\in\mathcal{S}$, $N\equiv1\pmod{n}$, and all elements are congruent to 1 mod $n$. Since they are positive integers, the largest ...
0
8,156.1875
-1
8,156.1875
The numbers 2, 3, 5, 7, 11, 13 are arranged in a multiplication table, with three along the top and the other three down the left. The multiplication table is completed and the sum of the nine entries is tabulated. What is the largest possible sum of the nine entries? \[ \begin{array}{c||c|c|c|} \times & a & b & c \...
420
0.9375
4,304.125
4,044.933333
8,192
Find the value of $\sin \frac{\pi}{7} \sin \frac{2\pi}{7} \sin \frac{3\pi}{7}$.
\frac{\sqrt{7}}{8}
0
6,742.5
-1
6,742.5
The percent that $M$ is greater than $N$ is:
\frac{100(M-N)}{N}
1. **Identify the Increase**: The difference $M - N$ represents the amount by which $M$ is greater than $N$. 2. **Convert to a Fraction**: To find out by what percent $M$ is greater than $N$, we need to express the increase as a fraction of $N$. This fraction is given by: \[ \frac{M-N}{N} \] 3. **Convert to ...
0
2,407.625
-1
2,407.625
Given $x^3y = k$ for a positive constant $k$, find the percentage decrease in $y$ when $x$ increases by $20\%$.
42.13\%
0.875
5,912.3125
5,642.071429
7,804
All the edges of the regular tetrahedron \(P-ABC\) have length \(1\). Let \( L, M, N \) be the midpoints of the edges \( PA, PB, PC \) respectively. Find the area of the cross-section of the circumsphere of the tetrahedron when cut by the plane \( LMN \).
\frac{\pi}{3}
0.625
7,255.4375
6,841
7,946.166667
Find the integer closest to $$\frac{1}{\sqrt[4]{5^{4}+1}-\sqrt[4]{5^{4}-1}}$$
250
Let $x=\left(5^{4}+1\right)^{1 / 4}$ and $y=\left(5^{4}-1\right)^{1 / 4}$. Note that $x$ and $y$ are both approximately 5. We have $$\frac{1}{x-y} =\frac{(x+y)\left(x^{2}+y^{2}\right)}{(x-y)(x+y)\left(x^{2}+y^{2}\right)}=\frac{(x+y)\left(x^{2}+y^{2}\right)}{x^{4}-y^{4}} =\frac{(x+y)\left(x^{2}+y^{2}\right)}{2} \approx ...
0.0625
8,192
8,192
8,192
Three equally spaced parallel lines intersect a circle, creating three chords of lengths $38, 38,$ and $34$. What is the distance between two adjacent parallel lines?
6
1. **Identify the setup and apply Stewart's Theorem**: We are given three equally spaced parallel lines intersecting a circle, creating three chords of lengths 38, 38, and 34. Let's denote the center of the circle as $O$, and the points where the chords intersect the circle as $C, D, E, F$ such that $CD$ and $EF$ are b...
0.375
7,188.1875
5,598.333333
8,142.1
Let the sum of the first $n$ terms of the sequence $\{a_n\}$ be $S_n$, where $S_n=n^2+n$, and the general term of the sequence $\{b_n\}$ is given by $b_n=x^{n-1}$. (1) Find the general term formula for the sequence $\{a_n\}$; (2) Let $c_n=a_nb_n$, and the sum of the first $n$ terms of the sequence $\{c_n\}$ be $T_n$....
\dfrac{1}{4}
0.625
6,656.6875
5,965.2
7,809.166667
How many five-character license plates consist of two consonants, followed by two vowels, and ending with a digit? (For this problem, consider Y is not a vowel.)
110,250
0
2,103.4375
-1
2,103.4375
The sides of a triangle have lengths $6.5$, $10$, and $s$, where $s$ is a whole number. What is the smallest possible value of $s$?
4
To find the smallest possible value of $s$ such that the sides $6.5$, $10$, and $s$ can form a triangle, we must apply the triangle inequality theorem. The triangle inequality theorem states that the sum of the lengths of any two sides of a triangle must be greater than the length of the third side. We need to check th...
1
1,773.9375
1,773.9375
-1
The sum of the series $\frac{3}{4} + \frac{5}{8} + \frac{9}{16} + \frac{17}{32} + \frac{33}{64} + \frac{65}{128} - 3.5$.
\frac{-1}{128}
0
6,353.625
-1
6,353.625
P.J. starts with \(m=500\) and chooses a positive integer \(n\) with \(1 \leq n \leq 499\). He applies the following algorithm to \(m\) and \(n\): P.J. sets \(r\) equal to the remainder when \(m\) is divided by \(n\). If \(r=0\), P.J. sets \(s=0\). If \(r>0\), P.J. sets \(s\) equal to the remainder when \(n\) is divide...
13
Suppose that \(m=500\) and \(1 \leq n \leq 499\) and \(1 \leq r \leq 15\) and \(2 \leq s \leq 9\) and \(t=0\). Since \(s>0\), then the algorithm says that \(t\) is the remainder when \(r\) is divided by \(s\). Since \(t=0\), then \(r\) is a multiple of \(s\). Thus, \(r=a s\) for some positive integer \(a\). Since \(r>0...
0
8,192
-1
8,192
Among the following propositions, the true one is marked by \_\_\_\_\_\_. \\((1)\\) The negation of the proposition "For all \\(x > 0\\), \\(x^{2}-x \leqslant 0\\)" is "There exists an \\(x > 0\\) such that \\(x^{2}-x > 0\\)." \\((2)\\) If \\(A > B\\), then \\(\sin A > \sin B\\). \\((3)\\) Given a sequence \\(\{a_{n}\}...
(1)
0.0625
6,850.375
3,051
7,103.666667
Xiaoming forgot how to write $egg$ and only remembered there were three letters $e$, $g$, $g$. He randomly wrote one of them. Calculate the probability that he wrote it correctly.
\frac{1}{3}
0.75
1,045.6875
723.916667
2,011
The sum of the first $n$ terms of a geometric sequence $\{a_n\}$, where each term is positive, is $S_n$. Given that $S_n = 2$ and $S_{3n} = 14$, calculate $S_{4n}$.
30
1
3,445.6875
3,445.6875
-1
Let \[f(x) = \frac{x^2 - 6x + 6}{2x - 4}\]and \[g(x) = \frac{ax^2 + bx + c}{x - d}.\]You are given the following properties: $\bullet$ The graphs of $f(x)$ and $g(x)$ have the same vertical asymptote. $\bullet$ The oblique asymptotes of $f(x)$ and $g(x)$ are perpendicular, and they intersect on the $y$-axis. $\bulle...
\left( 4, -\frac{1}{2} \right)
0.75
4,996.5625
3,931.416667
8,192
The lottery in our state consists of two drawings. First, a MegaBall is picked from among 27 numbered balls. Second, five WinnerBalls are picked from among 44 numbered balls. To win the lottery, you must pick the MegaBall number correctly and also pick the numbers on the five WinnerBalls (but you don't need to get th...
\dfrac{1}{29,\!322,\!216}
0
4,066.8125
-1
4,066.8125
Given an ellipse $\frac{x^{2}}{a^{2}}+\frac{y^{2}}{b^{2}}=1(a>b>0)$ with left and right foci $F_{1}(-c,0)$ and $F_{2}(c,0)$ respectively, and a point $P$ on the ellipse (different from the left and right vertices), the radius of the inscribed circle of $\triangle PF_{1}F_{2}$ is $r$. If the maximum value of $r$ is $\fr...
\frac{4}{5}
0.875
5,734.9375
5,383.928571
8,192
A positive integer $n$ not exceeding $120$ is chosen such that if $n\le 60$, then the probability of choosing $n$ is $p$, and if $n > 60$, then the probability of choosing $n$ is $2p$. The probability that a perfect square is chosen is? A) $\frac{1}{180}$ B) $\frac{7}{180}$ C) $\frac{13}{180}$ D) $\frac{1}{120}$ E) $\f...
\frac{13}{180}
0
3,553.9375
-1
3,553.9375
Let \(\triangle ABC\) be an isosceles right triangle with \(AB=AC=10\). Let \(M\) be the midpoint of \(BC\) and \(N\) the midpoint of \(BM\). Let \(AN\) hit the circumcircle of \(\triangle ABC\) again at \(T\). Compute the area of \(\triangle TBC\).
30
Note that since quadrilateral \(BACT\) is cyclic, we have \(\angle BTA=\angle BCA=45^{\circ}=\angle CBA=\angle CTA\). Hence, \(TA\) bisects \(\angle BTC\), and \(\angle BTC=90^{\circ}\). By the angle bisector theorem, we then have \(\frac{BT}{TC}=\frac{BN}{NC}=\frac{1}{3}\). By the Pythagorean theorem on right triangle...
1
4,237.75
4,237.75
-1
Given that α is an acute angle, cos(α+π/6) = 2/3, find the value of sinα.
\dfrac{\sqrt{15} - 2}{6}
0
6,390.875
-1
6,390.875
A pizza is cut into 10 pieces. Two of the pieces are each \(\frac{1}{24}\) of the whole pizza, four are each \(\frac{1}{12}\), two are each \(\frac{1}{8}\), and two are each \(\frac{1}{6}\). A group of \(n\) friends share the pizza by distributing all of these pieces. They do not cut any of these pieces. Each of the \(...
39
Each of the \(n\) friends is to receive \(\frac{1}{n}\) of the pizza. Since there are two pieces that are each \(\frac{1}{6}\) of the pizza and these pieces cannot be cut, then each friend receives at least \(\frac{1}{6}\) of the pizza. This means that there cannot be more than 6 friends; that is, \(n \leq 6\). Therefo...
0
7,229.75
-1
7,229.75
Find the smallest $n$ such that every subset of $\{1, 2, 3, . . . , 2004 \}$ with $n$ elements contains at least two elements that are relatively prime.
1003
0.5625
7,284.3125
6,578.333333
8,192
Two circles of radius $s$ are externally tangent to each other and internally tangent to the ellipse $x^2 + 4y^2 = 8.$ Find $s.$
\sqrt{\frac{3}{2}}
0
5,918.375
-1
5,918.375
Find the area bounded by the graph of $y = \arccos(\sin x)$ and the $x$-axis on the interval $\frac{\pi}{2} \le x \le \frac{5 \pi}{2}.$
\pi^2
0.4375
7,619.375
6,883.142857
8,192
[asy] fill(circle((4,0),4),grey); fill((0,0)--(8,0)--(8,-4)--(0,-4)--cycle,white); fill(circle((7,0),1),white); fill(circle((3,0),3),white); draw((0,0)--(8,0),black+linewidth(1)); draw((6,0)--(6,sqrt(12)),black+linewidth(1)); MP("A", (0,0), W); MP("B", (8,0), E); MP("C", (6,0), S); MP("D",(6,sqrt(12)), N); [/asy] In ...
1:4
0
4,927.5
-1
4,927.5
Meghana writes two (not necessarily distinct) primes $q$ and $r$ in base 10 next to each other on a blackboard, resulting in the concatenation of $q$ and $r$ (for example, if $q=13$ and $r=5$, the number on the blackboard is now 135). She notices that three more than the resulting number is the square of a prime $p$. F...
5
Trying $p=2$, we see that $p^{2}-3=1$ is not the concatenation of two primes, so $p$ must be odd. Then $p^{2}-3$ is even. Since $r$ is prime and determines the units digit of the concatenation of $q$ and $r, r$ must be 2. Then $p^{2}$ will have units digit 5, which means that $p$ will have units digit 5. Since $p$ is p...
0.1875
7,909
6,682.666667
8,192
In a parlor game, the magician asks one of the participants to think of a three digit number $(abc)$ where $a$, $b$, and $c$ represent digits in base $10$ in the order indicated. The magician then asks this person to form the numbers $(acb)$, $(bca)$, $(bac)$, $(cab)$, and $(cba)$, to add these five numbers, and to rev...
358
0.125
7,793.6875
5,005.5
8,192