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Triangles $\triangle DEF$ and $\triangle D'E'F'$ are in the coordinate plane with vertices $D(2,2)$, $E(2,14)$, $F(18,2)$, $D'(32,26)$, $E'(44,26)$, $F'(32,10)$. A rotation of $n$ degrees clockwise around the point $(u,v)$ where $0<n<180$, will transform $\triangle DEF$ to $\triangle D'E'F'$. Find $n+u+v$.
124
0
5,232.3125
-1
5,232.3125
In trapezoid $PQRS$ with $PQ$ parallel to $RS$, the diagonals $PR$ and $QS$ intersect at $T$. If the area of triangle $PQT$ is 75 square units, and the area of triangle $PST$ is 45 square units, what is the area of trapezoid $PQRS$?
192
0.25
7,169.3125
4,936.5
7,913.583333
The Fibonacci sequence is defined $F_1 = F_2 = 1$ and $F_n = F_{n - 1} + F_{n - 2}$ for all $n \ge 3.$ The Fibonacci numbers $F_a,$ $F_b,$ $F_c$ form an increasing arithmetic sequence. If $a + b + c = 2000,$ compute $a.$
665
0.375
7,391.5
6,057.333333
8,192
A point is equidistant from the coordinate axes if the vertical distance from the point to the $x$-axis is equal to the horizontal distance from the point to the $y$-axis. The point of intersection of the vertical line $x = a$ with the line with equation $3x + 8y = 24$ is equidistant from the coordinate axes. What is t...
-\frac{144}{55}
If $a > 0$, the distance from the vertical line with equation $x = a$ to the $y$-axis is $a$. If $a < 0$, the distance from the vertical line with equation $x = a$ to the $y$-axis is $-a$. In each case, there are exactly two points on the vertical line with equation $x = a$ that are also a distance of $a$ or $-a$ (as a...
1
3,717.9375
3,717.9375
-1
The two squares shown share the same center $O$ and have sides of length 1. The length of $\overline{AB}$ is $43/99$ and the area of octagon $ABCDEFGH$ is $m/n,$ where $m$ and $n$ are relatively prime positive integers. Find $m+n.$ [asy] //code taken from thread for problem real alpha = 25; pair W=dir(225), X=dir(315),...
185
0
8,192
-1
8,192
A triangle and a trapezoid are equal in area. They also have the same altitude. If the base of the triangle is 18 inches, the median of the trapezoid is:
9 \text{ inches}
1. **Identify the formula for the area of the triangle and trapezoid:** - The area of a triangle is given by the formula: \[ \text{Area}_{\text{triangle}} = \frac{1}{2} \times \text{base} \times \text{height} = \frac{1}{2}bh \] - The area of a trapezoid is given by the formula: \[ \text{A...
1
1,333.8125
1,333.8125
-1
A pyramid \( S A B C D \) has a trapezoid \( A B C D \) as its base, with bases \( B C \) and \( A D \). Points \( P_1, P_2, P_3 \) lie on side \( B C \) such that \( B P_1 < B P_2 < B P_3 < B C \). Points \( Q_1, Q_2, Q_3 \) lie on side \( A D \) such that \( A Q_1 < A Q_2 < A Q_3 < A D \). Let \( R_1, R_2, R_3, \) an...
2028
0.1875
8,147
7,952
8,192
Rectangle \(WXYZ\) is divided into four smaller rectangles. The perimeters of three of these smaller rectangles are 11, 16, and 19. The perimeter of the fourth rectangle lies between 11 and 19. What is the length of the perimeter of \(WXYZ\)? Options: A) 28 B) 30 C) 32 D) 38 E) 40
30
0
8,121.25
-1
8,121.25
$ABCD$ is a parallelogram with $\angle D$ obtuse. $M$ and $N$ are the feet of the perpendiculars from $D$ to $AB$ and $BC$ respectively. If $DB = DC = 50$ and $DA = 60$, find $DM + DN$.
88
0.3125
7,536.6875
6,959.4
7,799.090909
What is the least positive three-digit multiple of 7?
105
1
1,080.5625
1,080.5625
-1
Let $T_n$ be the sum of the reciprocals of the non-zero digits of the integers from $1$ to $5^n$ inclusive. Find the smallest positive integer $n$ for which $T_n$ is an integer.
504
0
8,192
-1
8,192
In $\triangle ABC$, $AB = 10$ and the height from $A$ to $BC$ is 3. When the product $AC \cdot BC$ is minimized, what is $AC + BC$?
4\sqrt{10}
0
8,192
-1
8,192
Among the four-digit numbers composed of the digits $0$, $1$, $2$, $3$, $4$, $5$ without repetition, there are a total of \_\_\_\_\_ numbers that are not divisible by $5$.
192
0.5625
6,000.125
4,417.444444
8,035
A cashier from Aeroflot has to deliver tickets to five groups of tourists. Three of these groups live in the hotels "Druzhba", "Rossiya", and "Minsk". The fourth group's address will be given by tourists from "Rossiya", and the fifth group's address will be given by tourists from "Minsk". In how many ways can the cashi...
30
0.375
6,084.0625
4,213.166667
7,206.6
Suppose there are 100 cookies arranged in a circle, and 53 of them are chocolate chip, with the remainder being oatmeal. Pearl wants to choose a contiguous subsegment of exactly 67 cookies and wants this subsegment to have exactly \(k\) chocolate chip cookies. Find the sum of the \(k\) for which Pearl is guaranteed to ...
71
We claim that the only values of \(k\) are 35 and 36. WLOG assume that the cookies are labelled 0 through 99 around the circle. Consider the following arrangement: cookies 0 through 17,34 through 50, and 67 through 84 are chocolate chip, and the remaining are oatmeal. (The cookies form six alternating blocks around the...
0
7,054.375
-1
7,054.375
For what value of the parameter \( p \) will the sum of the squares of the roots of the equation \[ p x^{2}+(p^{2}+p) x-3 p^{2}+2 p=0 \] be the smallest? What is this smallest value?
1.10
0
5,776.3125
-1
5,776.3125
If for any \( x \in \mathbf{R} \), the function \( f(x) \) satisfies the equation \( f(x+2009) = -f(x+2008) \), and \( f(2009) = -2009 \), determine the value of \( f(-1) \).
-2009
1
3,776.9375
3,776.9375
-1
In the line $8x + 5y + c = 0$, find the value of $c$ if the product of the $x$- and $y$- intercepts is $24$.
-8\sqrt{15}
0
3,642.6875
-1
3,642.6875
Simplify \[\frac{\sin 10^\circ + \sin 20^\circ + \sin 30^\circ + \sin 40^\circ + \sin 50^\circ + \sin 60^\circ + \sin 70^\circ + \sin 80^\circ}{\cos 5^\circ \cos 10^\circ \cos 20^\circ}.\]
4 \sqrt{2}
0.625
5,734.125
4,595.1
7,632.5
The number of positive integers from 1 to 2002 that contain exactly one digit 0.
414
0.3125
8,014.5625
7,624.2
8,192
Let $ABC$ be a non-equilateral triangle with integer sides. Let $D$ and $E$ be respectively the mid-points of $BC$ and $CA$ ; let $G$ be the centroid of $\Delta{ABC}$ . Suppose, $D$ , $C$ , $E$ , $G$ are concyclic. Find the least possible perimeter of $\Delta{ABC}$ .
37
0
8,192
-1
8,192
In triangle $\triangle ABC$, $A+B=5C$, $\sin \left(A-C\right)=2\sin B$. $(1)$ Find $A$; $(2)$ If $CM=2\sqrt{7}$ and $M$ is the midpoint of $AB$, find the area of $\triangle ABC$.
4\sqrt{3}
0.6875
6,005.5
5,334.727273
7,481.2
The graph of $xy = 4$ is a hyperbola. Find the distance between the foci of this hyperbola.
4\sqrt{2}
0
4,204.0625
-1
4,204.0625
The monkey has 100 bananas and its home is 50 meters away. The monkey can carry at most 50 bananas at a time and eats one banana for every meter walked. Calculate the maximum number of bananas the monkey can bring home.
25
0.0625
8,076.5625
6,345
8,192
Travis has to babysit the terrible Thompson triplets. Knowing that they love big numbers, Travis devises a counting game for them. First Tadd will say the number $1$, then Todd must say the next two numbers ($2$ and $3$), then Tucker must say the next three numbers ($4$, $5$, $6$), then Tadd must say the next four num...
5979
1. **Identify the pattern of numbers said by Tadd**: Tadd's turns involve saying an increasing number of consecutive numbers. The first few blocks of numbers Tadd says are: - 1st block: [1] - 2nd block: [7-10] (4 numbers) - 3rd block: [22-28] (7 numbers) - 4th block: [46-55] (10 numbers) 2. **Observe the p...
0.0625
6,888.5625
3,376
7,122.733333
Find the shortest distance between the point $(5,10)$ and the parabola given by the equation $x = \frac{y^2}{3}.$
\sqrt{53}
0
8,192
-1
8,192
Given vectors $\overset{→}{a}=(\cos x,-1+\sin x)$ and $\overset{→}{b}=(2\cos x,\sin x)$, (1) Express $\overset{→}{a}·\overset{→}{b}$ in terms of $\sin x$. (2) Find the maximum value of $\overset{→}{a}·\overset{→}{b}$ and the corresponding value of $x$.
\frac{9}{4}
0.375
4,037.1875
3,343.5
4,453.4
Let $n$ be a fixed positive integer. Determine the smallest possible rank of an $n \times n$ matrix that has zeros along the main diagonal and strictly positive real numbers off the main diagonal.
3
For $n=1$ the only matrix is (0) with rank 0. For $n=2$ the determinant of such a matrix is negative, so the rank is 2. We show that for all $n \geq 3$ the minimal rank is 3. Notice that the first three rows are linearly independent. Suppose that some linear combination of them, with coefficients $c_{1}, c_{2}, c_{3}$,...
0
8,192
-1
8,192
In the Cartesian coordinate system xOy, the polar equation of circle C is $\rho=4$. The parametric equation of line l, which passes through point P(1, 2), is given by $$\begin{cases} x=1+ \sqrt {3}t \\ y=2+t \end{cases}$$ (where t is a parameter). (I) Write the standard equation of circle C and the general equation of ...
11
0.9375
4,468.5
4,220.266667
8,192
A ball bounces back up $\frac{2}{3}$ of the height from which it falls. If the ball is dropped from a height of $243$ cm, after how many bounces does the ball first rise less than $30$ cm?
6
0.75
5,084.125
4,475.916667
6,908.75
Real numbers \( x, y, z \) satisfy \( x \geq y \geq z \geq 0 \) and \( 6x + 5y + 4z = 120 \). Find the sum of the maximum and minimum values of \( x + y + z \).
44
0.625
7,585.375
7,221.4
8,192
There is a reservoir A and a town B connected by a river. When the reservoir does not release water, the water in the river is stationary; when the reservoir releases water, the water in the river flows at a constant speed. When the reservoir was not releasing water, speedboat M traveled for 50 minutes from A towards B...
100/3
0.3125
5,319.125
4,706.4
5,597.636364
Given the set $$ M=\{1,2, \cdots, 2020\}, $$ for any non-empty subset $A$ of $M$, let $\lambda_{A}$ be the sum of the maximum and minimum numbers in the subset $A$. What is the arithmetic mean of all such $\lambda_{A}$?
2021
0.25
7,767.125
6,492.5
8,192
A magician and their assistant are planning to perform the following trick. A spectator writes a sequence of $N$ digits on a board. The magician's assistant covers two adjacent digits with a black circle. Then the magician enters. Their task is to guess both of the covered digits (and the order in which they are arrang...
101
0.1875
7,858.6875
6,414.333333
8,192
Find the maximum value of \[\frac{2x + 3y + 4}{\sqrt{x^2 + y^2 + 4}}\] over all real numbers $x$ and $y$.
\sqrt{29}
0
8,077.9375
-1
8,077.9375
The polynomial \[px^4 + qx^3 + rx^2 + sx + t = 0\] has coefficients that are all integers, and roots $-3$, $4$, $6$, and $\frac{1}{2}$. If $t$ is a positive integer, find its smallest possible value.
72
0.375
6,590.4375
5,252.666667
7,393.1
If the system of equations \begin{align*} 3x+y&=a,\\ 2x+5y&=2a, \end{align*} has a solution $(x,y)$ when $x=2$, compute $a$.
\frac{26}{3}
1
1,792.0625
1,792.0625
-1
Let $g(x) = |3\{x\} - 1.5|$ where $\{x\}$ denotes the fractional part of $x$. Determine the smallest positive integer $m$ such that the equation \[m g(x g(x)) = x\] has at least $3000$ real solutions.
23
0
8,192
-1
8,192
Let \( P \) be the midpoint of the height \( VH \) of a regular square pyramid \( V-ABCD \). If the distance from point \( P \) to a lateral face is 3 and the distance to the base is 5, find the volume of the regular square pyramid.
750
0.8125
5,071.1875
4,650.692308
6,893.333333
The number of digits in $4^{16}5^{25}$ (when written in the usual base $10$ form) is
28
1. **Rewrite the expression using properties of exponents:** The given expression is $4^{16}5^{25}$. We can express $4$ as $2^2$, so: \[ 4^{16} = (2^2)^{16} = 2^{32} \] Therefore, the expression becomes: \[ 4^{16}5^{25} = 2^{32}5^{25} \] 2. **Combine powers of 2 and 5 to form powers of 10:** ...
0.375
7,113.1875
5,315.166667
8,192
Let \( n = 2^3 \cdot 5^6 \cdot 8^9 \cdot 10^{10} \). How many natural-number factors does \( n \) have?
697
1
1,891.875
1,891.875
-1
Let $S$ be the set of positive integer divisors of $20^9.$ Three numbers are chosen independently and at random with replacement from the set $S$ and labeled $a_1,a_2,$ and $a_3$ in the order they are chosen. The probability that both $a_1$ divides $a_2$ and $a_2$ divides $a_3$ is $\tfrac{m}{n},$ where $m$ and $n$ are ...
77
Similar to before, we calculate that there are $190^3$ ways to choose $3$ factors with replacement. Then, we figure out the number of triplets ${a,b,c}$ and ${d,f,g}$, where $a$, $b$, and $c$ represent powers of $2$ and $d$, $f$, and $g$ represent powers of $5$, such that the triplets are in non-descending order. The m...
0.5
7,301.625
6,415.375
8,187.875
Ten women sit in $10$ seats in a line. All of the $10$ get up and then reseat themselves using all $10$ seats, each sitting in the seat she was in before or a seat next to the one she occupied before. In how many ways can the women be reseated?
89
To solve this problem, we will use a recursive approach to determine the number of ways the women can be reseated under the given constraints. We define $S_n$ as the number of ways $n$ women can be reseated in $n$ seats such that each woman sits in her original seat or in a seat adjacent to her original seat. #### Ste...
0.6875
5,727.4375
4,607.181818
8,192
The $8 \times 18$ rectangle $ABCD$ is cut into two congruent hexagons, as shown, in such a way that the two hexagons can be repositioned without overlap to form a square. What is $y$?
6
1. **Understanding the problem**: We are given an $8 \times 18$ rectangle that is cut into two congruent hexagons. These hexagons are rearranged to form a square. We need to find the value of $y$, which is a dimension in the hexagon. 2. **Area of the rectangle**: The area of the rectangle is calculated as: \[ \t...
0.75
5,884.5
5,445.833333
7,200.5
Alice and the White Rabbit left the Rabbit's house together at noon to go to the Duchess's reception. Halfway through, the Rabbit remembered that he forgot his gloves and fan, and ran back home at twice the speed he had been walking with Alice. Grabbing the gloves and fan, he then ran towards the Duchess (at the same s...
12:40
0.1875
5,175.6875
2,990.666667
5,679.923077
Given a parallelepiped \( A B C D A_{1} B_{1} C_{1} D_{1} \). On edge \( A_{1} D_{1} \), point \( X \) is selected, and on edge \( B C \), point \( Y \) is selected. It is known that \( A_{1} X = 5 \), \( B Y = 3 \), and \( B_{1} C_{1} = 14 \). The plane \( C_{1} X Y \) intersects the ray \( D A \) at point \( Z \). Fi...
20
0.3125
7,541.625
6,110.8
8,192
Let $a$, $b$, and $c$ be the $3$ roots of $x^3-x+1=0$. Find $\frac{1}{a+1}+\frac{1}{b+1}+\frac{1}{c+1}$.
-2
0.8125
4,980.4375
4,239.307692
8,192
Let $\omega$ be a fixed circle with radius 1, and let $B C$ be a fixed chord of $\omega$ such that $B C=1$. The locus of the incenter of $A B C$ as $A$ varies along the circumference of $\omega$ bounds a region $\mathcal{R}$ in the plane. Find the area of $\mathcal{R}$.
\pi\left(\frac{3-\sqrt{3}}{3}\right)-1
We will make use of the following lemmas. Lemma 1: If $A B C$ is a triangle with incenter $I$, then $\angle B I C=90+\frac{A}{2}$. Proof: Consider triangle $B I C$. Since $I$ is the intersection of the angle bisectors, $\angle I B C=\frac{B}{2}$ and $\angle I C B=\frac{C}{2}$. It follows that $\angle B I C=180-\frac{B}...
0
8,192
-1
8,192
The area of each of Art's cookies is given by the formula for the area of a trapezoid: A = 1/2h(b1 + b2). The total area of dough used by Art to make a batch of cookies is 240 square inches, and this is equivalent to the number of cookies multiplied by the area of each cookie. Let n represent the number of cookies in a...
24
0
502.375
-1
502.375
How many positive integers $n \leq 20000$ have the properties that $2n$ has 64 positive divisors including 1 and $2n$, and $5n$ has 60 positive divisors including 1 and $5n$?
4
Suppose $n=2^{r}5^{s}p_{3}^{a_{3}}p_{4}^{a_{4}}\cdots p_{k}^{a_{k}}$. Since $2n$ has 64 divisors and $5n$ has 60 divisors, $(r+2)(s+1)\left(a_{3}+1\right)\left(a_{4}+1\right)\cdots\left(a_{k}+1\right)=64$ and $(r+1)(s+2)\left(a_{3}+1\right)\left(a_{4}+1\right)\cdots\left(a_{k}+1\right)=60$. The common divisor of 64 and...
0
8,192
-1
8,192
What is the last two digits of the decimal representation of $9^{8^{7^{\cdot^{\cdot^{\cdot^{2}}}}}}$ ?
21
0.5625
7,058
6,176
8,192
Given that $S_{n}$ is the sum of the first $n$ terms of the sequence $\{a_{n}\}$, with $a_{1}=1$, $a_{2}=2$, $a_{3}=3$, and the sequence $\{a_{n}+a_{n+1}+a_{n+2}\}$ is an arithmetic sequence with a common difference of $2$, calculate the value of $S_{25}$.
269
0
7,599.375
-1
7,599.375
In a mathematics class, the probability of earning an A is 0.6 times the probability of earning a B, and the probability of earning a C is 1.6 times the probability of earning a B. The probability of earning a D is 0.3 times the probability of earning a B. Assuming that all grades are A, B, C, or D, how many B's will t...
14
0.125
6,838.5
4,187.5
7,217.214286
A small ball is released from a height \( h = 45 \) m without an initial velocity. The collision with the horizontal surface of the Earth is perfectly elastic. Determine the moment in time after the ball starts falling when its average speed equals its instantaneous speed. The acceleration due to gravity is \( g = 10 \...
4.24
0
7,182.125
-1
7,182.125
Suppose \( S = \{1,2, \cdots, 2005\} \). Find the minimum value of \( n \) such that every subset of \( S \) consisting of \( n \) pairwise coprime numbers contains at least one prime number.
16
0.0625
8,149.75
8,192
8,146.933333
Given that $\sin\alpha = \frac{1}{2} + \cos\alpha$, and $\alpha \in (0, \frac{\pi}{2})$, find the value of $\frac{\cos 2\alpha}{\sin(\alpha - \frac{\pi}{4})}$.
-\frac{\sqrt{14}}{2}
0
5,084
-1
5,084
Simplify: $(\sqrt{5})^4$.
25
1
1,541.8125
1,541.8125
-1
Calculate \(14 \cdot 31\) and \(\left\lfloor\frac{2+\sqrt{2}}{2}\right\rfloor + \left\lfloor\frac{3+\sqrt{3}}{3}\right\rfloor + \left\lfloor\frac{4+\sqrt{4}}{4}\right\rfloor + \cdots + \left\lfloor\frac{1989+\sqrt{1989}}{1989}\right\rfloor + \left\lfloor\frac{1990+\sqrt{1990}}{1990}\right\rfloor\).
1989
0
2,923.375
-1
2,923.375
$O$ is the center of square $A B C D$, and $M$ and $N$ are the midpoints of $\overline{B C}$ and $\overline{A D}$, respectively. Points $A^{\prime}, B^{\prime}, C^{\prime}, D^{\prime}$ are chosen on $\overline{A O}, \overline{B O}, \overline{C O}, \overline{D O}$, respectively, so that $A^{\prime} B^{\prime} M C^{\prim...
8634
Assume without loss of generality that the side length of $A B C D$ is 1 so that the area of the square is also 1 . This also means that $O M=O N=\frac{1}{2}$. As $A^{\prime} B^{\prime} M C^{\prime} D^{\prime} N$ is equiangular, it can be seen that $\angle A^{\prime} N O=60^{\circ}$, and also by symmetry, that $A^{\pri...
0
8,192
-1
8,192
\( x_{1} = 2001 \). When \( n > 1, x_{n} = \frac{n}{x_{n-1}} \). Given that \( x_{1} x_{2} x_{3} \ldots x_{10} = a \), find the value of \( a \).
3840
0.25
7,648.5625
6,018.25
8,192
A triangle $ABC$ with orthocenter $H$ is inscribed in a circle with center $K$ and radius $1$ , where the angles at $B$ and $C$ are non-obtuse. If the lines $HK$ and $BC$ meet at point $S$ such that $SK(SK -SH) = 1$ , compute the area of the concave quadrilateral $ABHC$ .
\frac{\sqrt{3}}{2}
0
8,192
-1
8,192
Two congruent cones with radius 12 cm and height 12 cm are enclosed within a cylinder. The base of each cone is a base of the cylinder, and the height of the cylinder is 24 cm. What is the number of cubic centimeters in the volume of the cylinder not occupied by the cones? Express your answer in terms of $\pi$.
2304\pi
1
2,238.5625
2,238.5625
-1
Each brick in the pyramid contains one number. Whenever possible, the number in each brick is the least common multiple of the numbers of the two bricks directly above it. What number could be in the bottom brick? Determine all possible options. (Hint: What is the least common multiple of three numbers, one of which ...
2730
0
8,185.625
-1
8,185.625
Determine the number of ways to arrange the letters of the word TARTAR.
90
1
1,784.9375
1,784.9375
-1
A ray starting from point $A(-4,1)$ reflects off the line $l_{1}: x-y+3=0$ and the reflected ray passes through point $B(-3,2)$. Find the slope of the line containing the reflected ray.
-3
0.4375
6,676.375
5,176.571429
7,842.888889
Consider a $3 \times 3$ grid of squares. A circle is inscribed in the lower left corner, the middle square of the top row, and the rightmost square of the middle row, and a circle $O$ with radius $r$ is drawn such that $O$ is externally tangent to each of the three inscribed circles. If the side length of each square i...
\frac{5 \sqrt{2}-3}{6}
Let $A$ be the center of the square in the lower left corner, let $B$ be the center of the square in the middle of the top row, and let $C$ be the center of the rightmost square in the middle row. It's clear that $O$ is the circumcenter of triangle $A B C$ - hence, the desired radius is merely the circumradius of trian...
0
6,344.625
-1
6,344.625
Given $|\vec{a}|=1$, $|\vec{b}|=6$, and $\vec{a}\cdot(\vec{b}-\vec{a})=2$, calculate the angle between $\vec{a}$ and $\vec{b}$.
\dfrac{\pi}{3}
0.125
1,667.5625
2,323.5
1,573.857143
For the ellipse $25x^2 - 100x + 4y^2 + 8y + 16 = 0,$ find the distance between the foci.
\frac{2\sqrt{462}}{5}
0
5,673.75
-1
5,673.75
Given that the center of the hyperbola is at the origin and one focus is F<sub>1</sub>(-$$\sqrt{5}$$, 0), if point P is on the hyperbola and the midpoint of segment PF<sub>1</sub> has coordinates (0, 2), then the equation of this hyperbola is _________ and its eccentricity is _________.
\sqrt{5}
0.8125
3,786.6875
2,933.461538
7,484
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?
\frac{1}{6}
0
3,747.0625
-1
3,747.0625
For each pair of distinct natural numbers \(a\) and \(b\), not exceeding 20, Petya drew the line \( y = ax + b \) on the board. That is, he drew the lines \( y = x + 2, y = x + 3, \ldots, y = x + 20, y = 2x + 1, y = 2x + 3, \ldots, y = 2x + 20, \ldots, y = 3x + 1, y = 3x + 2, y = 3x + 4, \ldots, y = 3x + 20, \ldots, y ...
190
0.125
7,650.5
7,404.5
7,685.642857
Given that $\theta$ is an angle in the second quadrant and $\tan(\theta + \frac{\pi}{4}) = \frac{1}{2}$, find the value of $\sin\theta + \cos\theta$.
-\frac{\sqrt{10}}{5}
0
5,455.125
-1
5,455.125
How many ways are there to put 4 balls in 3 boxes if the balls are distinguishable and the boxes are distinguishable?
81
0.9375
2,385.875
1,998.8
8,192
Given that the function $f(x)$ is an even function with a period of $2$, and when $x \in (0,1)$, $f(x) = 2^x - 1$, find the value of $f(\log_{2}{12})$.
-\frac{2}{3}
0
6,044.8125
-1
6,044.8125
A set containing three real numbers can be represented as $\{a,\frac{b}{a},1\}$, or as $\{a^{2}, a+b, 0\}$. Find the value of $a^{2023}+b^{2024}$.
-1
0.8125
3,991.4375
3,788.615385
4,870.333333
Let $\triangle ABC$ have sides $a$, $b$, and $c$ opposite to angles $A$, $B$, and $C$ respectively. Given that $\frac{{a^2 + c^2 - b^2}}{{\cos B}} = 4$. Find:<br/> $(1)$ $ac$;<br/> $(2)$ If $\frac{{2b\cos C - 2c\cos B}}{{b\cos C + c\cos B}} - \frac{c}{a} = 2$, find the area of $\triangle ABC$.
\frac{\sqrt{15}}{4}
0
6,691.5
-1
6,691.5
Xiaoming has several 1-yuan, 2-yuan, and 5-yuan banknotes. He wants to use no more than 10 banknotes to buy a kite priced at 18 yuan, and he must use at least two different denominations. How many different payment methods are possible?
11
0.125
7,269.125
7,067
7,298
Let $k$ be the product of every third positive integer from $2$ to $2006$ , that is $k = 2\cdot 5\cdot 8\cdot 11 \cdots 2006$ . Find the number of zeros there are at the right end of the decimal representation for $k$ .
168
0.1875
7,771.9375
7,715.333333
7,785
Given a bicycle's front tire lasts for 5000km and the rear tire lasts for 3000km, determine the maximum distance the bicycle can travel if the tires are swapped reasonably during use.
3750
0.3125
6,992.625
5,606.4
7,622.727273
Given a sequence \( x_{n} \), satisfying \( (n+1) x_{n+1}=x_{n}+n \), and \( x_{1}=2 \), find \( x_{2009} \).
\frac{2009! + 1}{2009!}
0
6,949.3125
-1
6,949.3125
Let $ABC$ be the triangle with vertices located at the center of masses of Vincent Huang's house, Tristan Shin's house, and Edward Wan's house; here, assume the three are not collinear. Let $N = 2017$ , and define the $A$ -*ntipodes* to be the points $A_1,\dots, A_N$ to be the points on segment $BC$ such that ...
2017^3 - 2
0
8,192
-1
8,192
How many different positive integers can be represented as a difference of two distinct members of the set $\{1, 2, 3, \ldots, 14, 15, 16 \}?$
15
0.9375
4,860.375
4,638.266667
8,192
Given that Erin the ant starts at a given corner of a hypercube (4-dimensional cube) and crawls along exactly 15 edges in such a way that she visits every corner exactly once and then finds that she is unable to return along an edge to her starting point, determine the number of paths that Erin can follow to meet these...
24
0.0625
7,636.0625
3,232
7,929.666667
Marvin had a birthday on Tuesday, May 27 in the leap year $2008$. In what year will his birthday next fall on a Saturday?
2017
To determine the next year when Marvin's birthday, May 27, falls on a Saturday after 2008, we need to consider the day of the week progression from 2008 onwards, taking into account whether each year is a leap year or not. 1. **Day Increment Calculation**: - In a non-leap year, there are 365 days, which is equivale...
0.25
7,643.8125
5,999.25
8,192
In a circle with center $O$, the measure of $\angle BAC$ is $45^\circ$, and the radius of the circle $OA=15$ cm. Also, $\angle BAC$ subtends another arc $BC$ which does not include point $A$. Compute the length of arc $BC$ in terms of $\pi$. [asy] draw(circle((0,0),1)); draw((0,0)--(sqrt(2)/2,sqrt(2)/2)--(-sqrt(2)/2,sq...
22.5\pi
0
1,999.125
-1
1,999.125
A cubical cake with edge length 3 inches is iced on the sides and the top. It is cut vertically into four pieces, such that one of the cut starts at the midpoint of the top edge and ends at a corner on the opposite edge. The piece whose top is triangular contains an area $A$ and is labeled as triangle $C$. Calculate th...
22.5
0
8,192
-1
8,192
A line with slope of $-2$ intersects the positive $x$-axis at $A$ and the positive $y$-axis at $B$. A second line intersects the $x$-axis at $C(8,0)$ and the $y$-axis at $D$. The lines intersect at $E(4,4)$. What is the area of the shaded quadrilateral $OBEC$? [asy] draw((0,-1)--(0,13)); draw((-1,0)--(10,0)); fill((0,...
40
1
4,363.125
4,363.125
-1
Given the function $y=\cos \left( 2x+\dfrac{\pi}{3} \right)$, determine the horizontal shift required to obtain its graph from the graph of the function $y=\cos 2x$.
\dfrac{\pi}{6}
0.75
3,913.9375
3,825.666667
4,178.75
Find the smallest constant $C$ such that for every real polynomial $P(x)$ of degree 3 that has a root in the interval $[0,1]$, \[ \int_0^1 \left| P(x) \right|\,dx \leq C \max_{x \in [0,1]} \left| P(x) \right|. \]
\frac{5}{6}
We prove that the smallest such value of $C$ is $5/6$. We first reduce to the case where $P$ is nonnegative in $[0,1]$ and $P(0) = 0$. To achieve this reduction, suppose that a given value $C$ obeys the inequality for such $P$. For $P$ general, divide the interval $[0,1]$ into subintervals $I_1,\dots,I_k$ at the roots ...
0
8,192
-1
8,192
Given that A is a moving point on the ray $x+y=0$ (where $x \leq 0$), and B is a moving point on the positive half of the x-axis, if line AB is tangent to the circle $x^2+y^2=1$, the minimum value of $|AB|$ is _______ .
2 + 2\sqrt{2}
0.125
8,103.6875
7,485.5
8,192
If two fair dice are tossed, what is the probability that their sum is divisible by 5 ?
\frac{1}{4}
$\frac{1}{4}$.
0
3,427.4375
-1
3,427.4375
Find the least positive integer $n$ satisfying the following statement: for eash pair of positive integers $a$ and $b$ such that $36$ divides $a+b$ and $n$ divides $ab$ it follows that $36$ divides both $a$ and $b$ .
1296
0
8,192
-1
8,192
The set $\{[x] + [2x] + [3x] \mid x \in \mathbb{R}\} \mid \{x \mid 1 \leq x \leq 100, x \in \mathbb{Z}\}$ has how many elements, where $[x]$ denotes the greatest integer less than or equal to $x$.
67
0
6,581.5
-1
6,581.5
Let \( f(x) \) be a function defined on \(\mathbf{R}\). Given that \( f(x) + x^{2} \) is an odd function and \( f(x) + 2^{x} \) is an even function, find the value of \( f(1) \).
-\frac{7}{4}
0.8125
5,375.75
4,725.846154
8,192
Find the smallest integer $k \geq 2$ such that for every partition of the set $\{2, 3,\hdots, k\}$ into two parts, at least one of these parts contains (not necessarily distinct) numbers $a$, $b$ and $c$ with $ab = c$.
32
We are tasked to find the smallest integer \( k \geq 2 \) such that every partition of the set \( \{2, 3, \ldots, k\} \) into two parts results in at least one part containing numbers \( a \), \( b \), and \( c \) such that \( ab = c \). To solve this, we will proceed with the following steps: 1. **Understand the Pa...
0
7,992.8125
-1
7,992.8125
Remove all perfect squares from the sequence of positive integers $1, 2, 3, \ldots$ to obtain a new sequence, and find the 2003rd term of this new sequence.
2048
0.75
6,198.9375
5,620.416667
7,934.5
Let point $O$ be inside $\triangle ABC$ and satisfy $4\overrightarrow{OA}+\overrightarrow{OB}+\overrightarrow{OC}=\overrightarrow{0}$. Determine the probability that a randomly thrown bean into $\triangle ABC$ lands in $\triangle OBC$.
\dfrac{2}{3}
0.75
5,833.9375
5,197.583333
7,743
At some time between 9:30 and 10 o'clock, the triangle determined by the minute hand and the hour hand is an isosceles triangle. If the two equal angles in this triangle are each twice as large as the third angle, what is the time?
9:36
0.0625
8,126
7,136
8,192
Triangle $ABC$ has a right angle at $C$ , and $D$ is the foot of the altitude from $C$ to $AB$ . Points $L, M,$ and $N$ are the midpoints of segments $AD, DC,$ and $CA,$ respectively. If $CL = 7$ and $BM = 12,$ compute $BN^2$ .
193
0.0625
8,130.625
7,210
8,192
Convert $6351_8$ to base 7.
12431_7
0.9375
5,024.0625
4,812.866667
8,192