Unnamed: 0
int64
0
40.3k
problem
stringlengths
10
5.15k
ground_truth
stringlengths
1
1.22k
solved_percentage
float64
0
100
25,000
Express $367_{8}+4CD_{13}$ as a base 10 integer, where $C$ and $D$ denote the digits whose values are 12 and 13, respectively, in base 13.
1079
0
25,001
Borya and Vova play the following game on an initially white $8 \times 8$ board. Borya goes first and, on each of his turns, colors any four white cells black. After each of his turns, Vova colors an entire row or column white. Borya aims to color as many cells black as possible, while Vova tries to hinder him. What is the maximum number of black cells that can be on the board after Borya's move, regardless of how Vova plays?
25
0.78125
25,002
Antônio needs to find a code with 3 different digits \( A, B, C \). He knows that \( B \) is greater than \( A \), \( A \) is less than \( C \), and also: \[ \begin{array}{cccc} & B & B \\ + & A & A \\ \hline & C & C \\ \end{array} = 242 \] What is the code that Antônio is looking for?
232
0
25,003
One face of a pyramid with a square base and all edges of length 2 is glued to a face of a regular tetrahedron with edge length 2 to form a polyhedron. What is the total edge length of the polyhedron?
18
2.34375
25,004
Two mutually perpendicular chords \( AB \) and \( CD \) are drawn in a circle. Determine the distance between the midpoint of segment \( AD \) and the line \( BC \), given that \( BD = 6 \), \( AC = 12 \), and \( BC = 10 \). If necessary, round your answer to two decimal places.
2.5
0.78125
25,005
Let equilateral triangle $ABC$ with side length $6$ be inscribed in a circle and let $P$ be on arc $AC$ such that $AP \cdot P C = 10$ . Find the length of $BP$ .
\sqrt{26}
1.5625
25,006
Let \( a, \) \( b, \) \( c \) be positive real numbers such that \[ \left( \frac{a}{b} + \frac{b}{c} + \frac{c}{a} \right) + \left( \frac{b}{a} + \frac{c}{b} + \frac{a}{c} \right) = 9. \] Find the minimum value of \[ \left( \frac{a}{b} + \frac{b}{c} + \frac{c}{a} \right) \left( \frac{b}{a} + \frac{c}{b} + \frac{a}{c} \right). \]
57
0
25,007
Suppose $\csc y + \cot y = \frac{25}{7}$ and $\sec y + \tan y = \frac{p}{q}$, where $\frac{p}{q}$ is in lowest terms. Find $p+q$.
29517
0
25,008
Let $p(x)$ be a polynomial of degree strictly less than $100$ and such that it does not have $(x^3-x)$ as a factor. If $$ \frac{d^{100}}{dx^{100}}\bigg(\frac{p(x)}{x^3-x}\bigg)=\frac{f(x)}{g(x)} $$ for some polynomials $f(x)$ and $g(x)$ then find the smallest possible degree of $f(x)$ .
200
1.5625
25,009
Given that the radius of circle $O$ is $2$, and its inscribed triangle $ABC$ satisfies $c^{2}-a^{2}=4( \sqrt {3}c-b)\sin B$, where $a$, $b$, and $c$ are the sides opposite to angles $A$, $B$, and $C$, respectively. (I) Find angle $A$; (II) Find the maximum area $S$ of triangle $ABC$.
2+\sqrt{3}
59.375
25,010
Trapezoid $EFGH$ has sides $EF=105$, $FG=45$, $GH=21$, and $HE=80$, with $EF$ parallel to $GH$. A circle with center $Q$ on $EF$ is drawn tangent to $FG$ and $HE$. Find the exact length of $EQ$ using fractions.
\frac{336}{5}
0
25,011
Given that $\angle C=90^{\circ}$, \(A D=D B\), \(D E \perp A B\), \(A B=20\), and \(A C=12\), find the area of quadrilateral \(AD EC\).
58 \frac{1}{2}
0
25,012
In a similar setup, square $PQRS$ is constructed along diameter $PQ$ of a semicircle. The semicircle and square $PQRS$ are coplanar. Line segment $PQ$ has a length of 8 centimeters. If point $N$ is the midpoint of arc $PQ$, what is the length of segment $NS$?
4\sqrt{10}
3.90625
25,013
Each of $1000$ elves has a hat, red on the inside and blue on the outside or vise versa. An elf with a hat that is red outside can only lie, and an elf with a hat that is blue outside can only tell the truth. One day every elf tells every other elf, “Your hat is red on the outside.” During that day, some of the elves turn their hats inside out at any time during the day. (An elf can do that more than once per day.) Find the smallest possible number of times any hat is turned inside out.
998
0
25,014
The area of the large square \(ABCD\) in the diagram is 1, and the other points are the midpoints of the sides. Question: What is the area of the shaded triangle?
\frac{3}{32}
0
25,015
Let $\theta = 25^\circ$ be an angle such that $\tan \theta = \frac{1}{6}$. Compute $\sin^6 \theta + \cos^6 \theta$.
\frac{11}{12}
0
25,016
A sphere intersects the $xy$-plane in a circle centered at $(2, 3, 0)$ with radius 2. The sphere also intersects the $yz$-plane in a circle centered at $(0, 3, -8),$ with radius $r.$ Find $r.$
2\sqrt{15}
0
25,017
Calculate the volume of tetrahedron PQRS with edge lengths PQ = 4, PR = 5, PS = 6, QR = 3, QS = √37, and RS = 7.
10.25
0
25,018
If $8^x - 8^{x-1} = 60$, calculate the value of $(3x)^x$.
58.9
0
25,019
(Full score: 8 points) During the 2010 Shanghai World Expo, there were as many as 11 types of admission tickets. Among them, the price for a "specified day regular ticket" was 200 yuan per ticket, and the price for a "specified day concession ticket" was 120 yuan per ticket. A ticket sales point sold a total of 1200 tickets of these two types on the opening day, May 1st, generating a revenue of 216,000 yuan. How many tickets of each type were sold by this sales point on that day?
300
10.9375
25,020
In triangle $ABC$, the sides opposite angles $A$, $B$, and $C$ are $a$, $b$, and $c$ respectively, and $(a+b)(\sin A - \sin B) = (c-b)\sin C.$ (1) Determine the measure of angle $A$. (2) If $2c=3b$ and the area of $\triangle ABC$ is $6 \sqrt{3}$, find the value of $a$.
\frac{2\sqrt{21}}{3}
0
25,021
Find the smallest four-digit number that satisfies the following system of congruences: \begin{align*} 3x &\equiv 6 \pmod{12} \\ 5x + 20 &\equiv 25 \pmod{15} \\ 3x - 2 &\equiv 2x \pmod{35} \end{align*}
1274
0
25,022
Compute the value of $$64^{-\frac{1}{3}}+lg0.001$$.
- \frac{11}{2}
0
25,023
The total number of workers in Workshop A and Workshop C is $x + y$. If a sample of 45 people is drawn from the factory with 20 people from Workshop A and 10 people from Workshop C, determine the relationship between the number of workers in Workshop A, Workshop B, and Workshop C.
900
0
25,024
Squares of integers that are palindromes (i.e., they read the same left-to-right and right-to-left) are an interesting subject of study. For example, the squares of $1, 11, 111,$ and $1111$ are $1, 121, 12321,$ and $1234321$ respectively, and all these numbers are palindromes. This rule applies to any number of ones up to 9. However, there are irregular cases, such as $264^2 = 69696$ and $2285^2 = 5221225$. In all the above examples, the number of digits is odd. Could the reader provide examples with an even number of digits?
698896
71.875
25,025
A numismatist has 100 identical-looking coins, knowing that among them are 30 genuine coins and 70 counterfeit coins. The masses of all genuine coins are the same, while the masses of all counterfeit coins are different, with each counterfeit coin being heavier than a genuine coin. The exact masses of the coins are unknown. There is a two-pan balance scale available, which can be used to compare the masses of two groups of coins that have the same number of coins. What is the minimum number of weighings needed for the numismatist to reliably find at least one genuine coin?
70
0
25,026
The sum of n terms of an arithmetic progression is 180, and the common difference is 3. If the first term must be a positive integer, and n > 1, then find the number of possible values for n.
14
0.78125
25,027
To investigate the growth inhibitory effect of a certain drug on mice, $40$ mice were divided into two groups, a control group (without the drug) and an experimental group (with the drug).<br/>$(1)$ Suppose the number of mice in the control group among two mice is $X$, find the probability distribution and mathematical expectation of $X$;<br/>$(2)$ The weights of the $40$ mice are as follows (unit: $g) (already arranged in ascending order):<br/>Control group: $17.3, 18.4, 20.1, 20.4, 21.5, 23.2, 24.6, 24.8, 25.0, 25.4$<br/>$26.1, 26.3, 26.4, 26.5, 26.8, 27.0, 27.4, 27.5, 27.6, 28.3$<br/>Experimental group: $5.4, 6.6, 6.8, 6.9, 7.8, 8.2, 9.4, 10.0, 10.4, 11.2$<br/>$14.4, 17.3, 19.2, 20.2, 23.6, 23.8, 24.5, 25.1, 25.2, 26.0$<br/>$(i)$ Find the median $m$ of the weights of the $40$ mice and complete the following $2\times 2$ contingency table:<br/><table><tbody><tr><td align="center"></td><td align="center">$ \lt m$</td><td align="center">$\geq m$</td></tr><tr><td align="center">Control Group</td><td align="center">_____</td><td align="center">_____</td></tr><tr><td align="center">Experimental Group</td><td align="center">_____</td><td align="center">_____</td></tr></tbody></table>$($ii)$ Based on the $2\times 2$ contingency table, can we be $95\%$ confident that the drug inhibits the growth of mice.<br/>Reference data:<br/><table><tbody><tr><td align="center">$k_{0}$</td><td align="center">$0.10$</td><td align="center">$0.05$</td><td align="center">$0.010$</td></tr><tr><td align="center">$P(k^{2}\ge k_{0})$</td><td align="center">$2.706$</td><td align="center">$3.841$</td><td align="center">$6.635$</td></tr></tbody></table>
95\%
0
25,028
Given that $\cos ( \frac {π}{6}+α) \cdot \cos ( \frac {π}{3}-α)=- \frac {1}{4}$, where $α \in ( \frac {π}{3}, \frac {π}{2})$, find the value of $\sin 2α$ and the value of $\tan α - \frac {1}{\tan α}$.
\frac{2\sqrt{3}}{3}
2.34375
25,029
The escalator of the department store, which at any given time can be seen at $75$ steps section, moves up one step in $2$ seconds. At time $0$ , Juku is standing on an escalator step equidistant from each end, facing the direction of travel. He goes by a certain rule: one step forward, two steps back, then again one step forward, two back, etc., taking one every second in increments of one step. Which end will Juku finally get out and at what point will it happen?
23
0
25,030
Find the largest positive integer $N $ for which one can choose $N $ distinct numbers from the set ${1,2,3,...,100}$ such that neither the sum nor the product of any two different chosen numbers is divisible by $100$ . Proposed by Mikhail Evdokimov
44
0
25,031
Let \( x \) and \( y \) be positive integers, with \( x < y \). The leading digit of \( \lg x \) is \( a \), and the trailing digit is \( \alpha \); the leading digit of \( \lg y \) is \( b \), and the trailing digit is \( \beta \). They satisfy the conditions \( a^{2} + b^{2} = 5 \) and \( \alpha + \beta = 1 \). What is the maximum value of \( x \)?
80
0.78125
25,032
What is the smallest positive integer $n$ such that $\frac{1}{n}$ is a terminating decimal and $n$ contains the digit '3'?
3125
0
25,033
Find the sum of all positive integers $n$ such that, given an unlimited supply of stamps of denominations $7, n,$ and $n+2$ cents, $120$ cents is the greatest postage that cannot be formed.
22
0
25,034
Express the sum of $0.\overline{123}+0.\overline{0123}+0.\overline{000123}$ as a common fraction.
\frac{123 \times 1000900}{999 \times 9999 \times 100001}
0
25,035
A factory implements a time-based wage system, where each worker is paid 6 yuan for every hour worked, for a total of 8 hours per day. However, the clock used for timing is inaccurate: it takes 69 minutes for the minute hand to coincide with the hour hand once. Calculate the amount of wages underpaid to each worker per day.
2.60
0
25,036
Let $p,$ $q,$ $r,$ $s$ be distinct real numbers such that the roots of $x^2 - 12px + 13q = 0$ are $r$ and $s,$ and the roots of $x^2 - 12rx - 13s = 0$ are $p$ and $q.$ Find the value of $p + q + r + s.$
2028
18.75
25,037
Given that $a, b, c$ are the sides opposite to angles $A, B, C$ respectively in $\triangle ABC$, and $\cos A \sin B \sin C + \cos B \sin A \sin C = 2 \cos C \sin A \sin B$, find the maximum value of $C$.
\frac{\pi}{3}
64.84375
25,038
A right rectangular prism $Q$ has integral side lengths $a, b, c$ with $a \le b \le c$. A plane parallel to one of the faces of $Q$ cuts $Q$ into two prisms, one of which is similar to $Q$, with both having nonzero volumes. The middle side length $b = 3969$. Determine the number of ordered triples $(a, b, c)$ that allow such a plane to exist.
12
0
25,039
A solid cube of side length 4 cm is cut into two pieces by a plane that passed through the midpoints of six edges. Find the surface area of each half cube created.
69
0
25,040
The increasing sequence of positive integers $b_1, b_2, b_3, \ldots$ follows the rule: \[ b_{n + 2} = b_{n + 1} + b_n \] for all $n \geq 1$. If $b_5 = 55$, find $b_6$.
84
0.78125
25,041
A conical flask has a base radius of $15$ cm and a height of $30$ cm. The flask is filled with a liquid to a height of $10$ cm from the base, and a sphere is inscribed such that it just touches the liquid surface. What is the radius of the sphere? Express your answer in cm.
10
7.8125
25,042
Let $\phi = \tfrac{1+\sqrt 5}2$ be the positive root of $x^2=x+1$ . Define a function $f:\mathbb N\to\mathbb N$ by \begin{align*} f(0) &= 1 f(2x) &= \lfloor\phi f(x)\rfloor f(2x+1) &= f(2x) + f(x). \end{align*} Find the remainder when $f(2007)$ is divided by $2008$ .
2007
0
25,043
Given that $\alpha$ and $\beta$ are the roots of $x^2 - 3x + 1 = 0,$ find $7 \alpha^5 + 8 \beta^4.$
1448
0
25,044
In triangle $ABC$, $M$ is the midpoint of $\overline{BC}$, $AB = 15$, and $AC = 24$. Let $E$ be a point on $\overline{AC}$, and $H$ be a point on $\overline{AB}$, and let $G$ be the intersection of $\overline{EH}$ and $\overline{AM}$. If $AE = 3AH$, find $\frac{EG}{GH}$.
\frac{2}{3}
2.34375
25,045
Given point $P(2,2)$, and circle $C$: $x^{2}+y^{2}-8y=0$. A moving line $l$ passing through point $P$ intersects circle $C$ at points $A$ and $B$, with the midpoint of segment $AB$ being $M$, and $O$ being the origin. $(1)$ Find the equation of the trajectory of point $M$; $(2)$ When $|OP|=|OM|$, find the equation of line $l$ and the area of $\Delta POM$.
\frac{16}{5}
0.78125
25,046
Find the area of the triangle (see the diagram) on graph paper. (Each side of a square is 1 unit.)
1.5
0
25,047
The product of three positive integers $a$, $b$, and $c$ equals 1176. What is the minimum possible value of the sum $a + b + c$?
59
0
25,048
Find real numbers \( x, y, z \) greater than 1 that satisfy the equation \[ x + y + z + \frac{3}{x - 1} + \frac{3}{y - 1} + \frac{3}{z - 1} = 2(\sqrt{x + 2} + \sqrt{y + 2} + \sqrt{z + 2}). \]
\frac{3 + \sqrt{13}}{2}
0.78125
25,049
5 points in a plane are situated so that no two of the lines joining a pair of points are coincident, parallel, or perpendicular. Through each point, lines are drawn perpendicular to each of the lines through two of the other 4 points. Determine the maximum number of intersections these perpendiculars can have.
315
0
25,050
In a dark room drawer, there are 100 red socks, 80 green socks, 60 blue socks, and 40 black socks. A young person picks out one sock at a time without seeing its color. To ensure that at least 10 pairs of socks are obtained, what is the minimum number of socks they must pick out? (Assume that two socks of the same color make a pair, and a single sock cannot be used in more than one pair) (37th American High School Mathematics Examination, 1986)
23
1.5625
25,051
For the function $y=f(x)$, if there exists $x_{0} \in D$ such that $f(-x_{0})+f(x_{0})=0$, then the function $f(x)$ is called a "sub-odd function" and $x_{0}$ is called a "sub-odd point" of the function. Consider the following propositions: $(1)$ Odd functions are necessarily "sub-odd functions"; $(2)$ There exists an even function that is a "sub-odd function"; $(3)$ If the function $f(x)=\sin (x+ \frac {\pi}{5})$ is a "sub-odd function", then all "sub-odd points" of this function are $\frac {k\pi}{2} (k\in \mathbb{Z})$; $(4)$ If the function $f(x)=\lg \frac {a+x}{1-x}$ is a "sub-odd function", then $a=\pm1$; $(5)$ If the function $f(x)=4^{x}-m\cdot 2^{x+1}$ is a "sub-odd function", then $m\geqslant \frac {1}{2}$. Among these, the correct propositions are ______. (Write down the numbers of all propositions you think are correct)
(1)(2)(4)(5)
0
25,052
Given the function $g(x) = \frac{6x^2 + 11x + 17}{7(2 + x)}$, find the minimum value of $g(x)$ for $x \ge 0$.
\frac{127}{24}
0
25,053
Given that Jessica uses 150 grams of lemon juice and 100 grams of sugar, and there are 30 calories in 100 grams of lemon juice and 386 calories in 100 grams of sugar, and water contains no calories, compute the total number of calories in 300 grams of her lemonade.
152.1
0
25,054
The number 123456789 is written on the board. Two adjacent digits are selected from the number, if neither of them is 0, 1 is subtracted from each digit, and the selected digits are swapped (for example, from 123456789, one operation can result in 123436789). What is the smallest number that can be obtained as a result of these operations?
101010101
0.78125
25,055
The region shown is bounded by the arcs of circles having radius 5 units, each with a central angle measure of 45 degrees, intersecting at points of tangency. The area of the region can be expressed in the form $a\sqrt{b} + c\pi$ square units, where $\sqrt{b}$ is a radical in simplest form. Calculate the value of $a + b + c$.
-12.625
0
25,056
What percent of the palindromes between 1000 and 2000 contain at least one 7?
12\%
0
25,057
What is the smallest four-digit number that is divisible by $35$?
1200
0
25,058
A function $g$ from the integers to the integers is defined as follows: \[g(n) = \left\{ \begin{array}{cl} n + 5 & \text{if $n$ is odd}, \\ n/2 & \text{if $n$ is even}. \end{array} \right.\] Suppose $m$ is odd and $g(g(g(m))) = 39.$ Find $m.$
63
7.8125
25,059
A factory estimates that the total demand for a particular product in the first $x$ months starting from the beginning of 2016, denoted as $f(x)$ (in units of 'tai'), is approximately related to the month $x$ as follows: $f(x)=x(x+1)(35-2x)$, where $x \in \mathbb{N}^*$ and $x \leqslant 12$. (1) Write the relationship expression between the demand $g(x)$ in the $x$-th month of 2016 and the month $x$; (2) If the factory produces $a$ 'tai' of this product per month, what is the minimum value of $a$ to ensure that the monthly demand is met?
171
0
25,060
Evaluate the expression \[ \frac{a^2 + 2a}{a^2 + a} \cdot \frac{b^2 - 4}{b^2 - 6b + 8} \cdot \frac{c^2 + 16c + 64}{c^2 + 12c + 36} \] given that \(c = b - 20\), \(b = a + 4\), \(a = 2\), and ensuring none of the denominators are zero.
\frac{3}{4}
0
25,061
Find the largest negative root of the equation $$ 4 \sin (3 x) + 13 \cos (3 x) = 8 \sin (x) + 11 \cos (x) $$
-0.1651
0
25,062
Consider the integer \[M = 8 + 88 + 888 + 8888 + \cdots + \underbrace{88\ldots 88}_\text{150 digits}.\] Find the sum of the digits of $M$.
300
0
25,063
Let \( p, q, r, s, t, u, v, \) and \( w \) be real numbers such that \( pqrs = 16 \) and \( tuvw = 25 \). Find the minimum value of \[ (pt)^2 + (qu)^2 + (rv)^2 + (sw)^2. \]
400
4.6875
25,064
What is the value of the sum $\frac{3}{4}+\frac{3^2}{4^2}+\frac{3^3}{4^3}+ \ldots +\frac{3^{15}}{4^{15}}$? Express your answer as a common fraction.
\frac{3177884751}{1073741824}
0
25,065
Given vectors $\overrightarrow{a}=( \sqrt {3}\sin x,m+\cos x)$ and $\overrightarrow{b}=(\cos x,-m+\cos x)$, and the function $f(x)= \overrightarrow{a}\cdot \overrightarrow{b}$ (1) Find the analytical expression for the function $f(x)$; (2) When $x\in\left[-\frac{\pi}{6}, \frac{\pi}{3}\right]$, the minimum value of $f(x)$ is $-4$. Find the maximum value of the function $f(x)$ and the corresponding value of $x$ in this interval.
-\frac{3}{2}
0
25,066
Consider the following sequence of sets of natural numbers. The first set \( I_{0} \) consists of two ones, 1,1. Then, between these numbers, we insert their sum \( 1+1=2 \); we obtain the set \( I_{1}: 1,2,1 \). Next, between each pair of numbers in \( I_{1} \) we insert their sum; we obtain the set \( I_{2}: 1,3,2,3,1 \). Proceeding in the same way with the set \( I_{2} \), we obtain the set \( I_{3}: 1,4,3,5,2,5,3,4,1 \), and so on. How many times will the number 1973 appear in the set \( I_{1000000} \)?
1972
0
25,067
Given that \(a, b, c, a+b-c, a+c-b, b+c-a, a+b+c\) are 7 distinct prime numbers, and the sum of any two of \(a, b, c\) is 800. Let \(d\) be the difference between the largest and smallest of these 7 prime numbers. Find the maximum possible value of \(d\).
1594
42.96875
25,068
In a 10 by 10 table \(A\), some numbers are written. Let \(S_1\) be the sum of all numbers in the first row, \(S_2\) in the second row, and so on. Similarly, let \(t_1\) be the sum of all numbers in the first column, \(-t_2\) in the second column, and so on. A new table \(B\) of size 10 by 10 is created with numbers written as follows: in the first cell of the first row, the smaller of \(S_1\) and \(t_1\) is written, in the third cell of the fifth row, the smaller of \(S_5\) and \(t_3\) is written, and similarly the entire table is filled. It turns out that it is possible to number the cells of table \(B\) from 1 to 100 such that in the cell with number \(k\), the number will be less than or equal to \(k\). What is the maximum value that the sum of all numbers in table \(A\) can take under these conditions?
21
0
25,069
The arithmetic mean of a set of $60$ numbers is $42$. If three numbers from the set, $48$, $58$, and $52$, are removed, find the arithmetic mean of the remaining set of numbers.
41.4
0
25,070
Given a triangle $ABC$ with the sides opposite to angles $A$, $B$, $C$ denoted by $a$, $b$, $c$ respectively, let vectors $\overrightarrow{m}=(1-\cos(A+B), \cos \frac{A-B}{2})$ and $\overrightarrow{n}=(\frac{5}{8}, \cos \frac{A-B}{2})$, and it's known that $\overrightarrow{m} \cdot \overrightarrow{n} = \frac{9}{8}$. 1. Find the value of $\tan A \cdot \tan B$. 2. Find the maximum value of $\frac{a b \sin C}{a^2 + b^2 - c^2}$.
-\frac{3}{8}
5.46875
25,071
A larger equilateral triangle ABC with side length 5 has a triangular corner DEF removed from one corner, where DEF is an isosceles triangle with DE = EF = 2, and DF = 2\sqrt{2}. Calculate the perimeter of the remaining quadrilateral.
16
8.59375
25,072
What is the probability of rolling eight standard, six-sided dice and getting exactly three pairs of identical numbers, while the other two numbers are distinct from each other and from those in the pairs? Express your answer as a common fraction.
\frac{525}{972}
0
25,073
The graph of $y=g(x)$, defined on a limited domain shown, is conceptualized through the function $g(x) = \frac{(x-6)(x-4)(x-2)(x)(x+2)(x+4)(x+6)}{945} - 2.5$. If each horizontal grid line represents a unit interval, determine the sum of all integers $d$ for which the equation $g(x) = d$ has exactly six solutions.
-5
15.625
25,074
There are 8 Olympic volunteers, among them volunteers $A_{1}$, $A_{2}$, $A_{3}$ are proficient in Japanese, $B_{1}$, $B_{2}$, $B_{3}$ are proficient in Russian, and $C_{1}$, $C_{2}$ are proficient in Korean. One volunteer proficient in Japanese, Russian, and Korean is to be selected from them to form a group. (Ⅰ) Calculate the probability of $A_{1}$ being selected; (Ⅱ) Calculate the probability that neither $B_{1}$ nor $C_{1}$ is selected.
\dfrac {5}{6}
0.78125
25,075
If $q(x) = x^5 - 4x^3 + 5$, then find the coefficient of the $x^3$ term in the polynomial $(q(x))^2$.
40
0
25,076
There are $n$ mathematicians attending a conference. Each mathematician has exactly 3 friends (friendship is mutual). If they are seated around a circular table such that each person has their friends sitting next to them on both sides, the number of people at the table is at least 7. Find the minimum possible value of $n$.
24
0
25,077
A train is scheduled to arrive at a station randomly between 1:00 PM and 3:00 PM, and it waits for 15 minutes before leaving. If Alex arrives at the station randomly between 1:00 PM and 3:00 PM as well, what is the probability that he will find the train still at the station when he arrives?
\frac{105}{1920}
0
25,078
Given vectors $\mathbf{a} = \begin{pmatrix} 2 \\ 3 \\ 1 \end{pmatrix}$ and $\mathbf{b} = \begin{pmatrix} 1 \\ -2 \\ 0 \end{pmatrix},$ determine the scalar $s$ such that \[\begin{pmatrix} 5 \\ -4 \\ 1 \end{pmatrix} = s(\mathbf{a} \times \mathbf{b}) + p\mathbf{a} + q\mathbf{b},\] where $p$ and $q$ are scalars.
-\frac{1}{45}
0
25,079
Calculate the value of $\frac{17!}{7!10!}$.
408408
0
25,080
The polynomial \( x^{103} + Cx + D \) is divisible by \( x^2 + 2x + 1 \) for some real numbers \( C \) and \( D \). Find \( C + D \).
-1
0
25,081
Find the smallest three-digit number in a format $abc$ (where $a, b, c$ are digits, $a \neq 0$) such that when multiplied by 111, the result is not a palindrome.
105
0
25,082
In the Cartesian coordinate system $xOy$, the parametric equation of curve $C_{1}$ is $\begin{cases}x=a\cos \varphi \\ y=b\sin \varphi\end{cases} (a > b > 0,$ $\varphi$ is the parameter), and the point $M(2, \sqrt{3})$ on curve $C1$ corresponds to the parameter $\varphi= \frac{\pi}{3}$. Using $O$ as the pole and the positive half-axis of $x$ as the polar axis to establish a polar coordinate system, curve $C2$ is a circle with its center on the polar axis and passing through the pole. The ray $\theta= \frac{\pi}{4}$ intersects curve $C2$ at point $D(\sqrt{2}, \frac{\pi}{4})$. $(1)$ Find the standard equation of curve $C1$ and the polar equation of curve $C2$; $(2)$ If $A(\rho_{1},\theta),B(\rho_{2},\theta+ \frac{\pi}{2})$ are two points on curve $C1$, find the value of $\frac{1}{\rho_{1}^{2}+\rho_{2}^{2}}$.
\frac{5}{16}
0
25,083
Evaluate the expression: $2\log_{2}\;\sqrt {2}-\lg 2-\lg 5+ \frac{1}{ 3(\frac{27}{8})^{2} }$.
\frac{4}{9}
0
25,084
If the graph of the linear function $y=(7-m)x-9$ does not pass through the second quadrant, and the fractional equation about $y$ $\frac{{2y+3}}{{y-1}}+\frac{{m+1}}{{1-y}}=m$ has a non-negative solution, calculate the sum of all integer values of $m$ that satisfy the conditions.
14
0
25,085
Find the smallest positive number $\lambda$ such that for any triangle with side lengths $a, b, c$, given $a \geqslant \frac{b+c}{3}$, it holds that $$ a c + b c - c^{2} \leqslant \lambda\left(a^{2} + b^{2} + 3 c^{2} + 2 a b - 4 b c\right). $$
\frac{2\sqrt{2} + 1}{7}
0
25,086
It is known that the center C of a moving circle is on the parabola $x^2=2py$ ($p>0$), the circle passes through point A $(0, p)$, and intersects the x-axis at two points M and N. The maximum value of $\sin\angle MCN$ is.
\frac{1}{\sqrt{2}}
0.78125
25,087
Let $s(\theta) = \frac{1}{2 - \theta}$. What is $s(s(s(s(s(s(s(s(s(\frac{1}{2})))))))))$ (where $s$ is applied 9 times)?
\frac{13}{15}
0
25,088
A cube of mass $m$ slides down the felt end of a ramp semicircular of radius $h$ , reaching a height $h/2$ at the opposite extreme. Find the numerical coefficient of friction $\mu_k$ bretween the cube and the surface. *Proposed by Danilo Tejeda, Atlantida*
\frac{1}{\sqrt{1 - \left(\frac{1}{2\pi}\right)^2}}
0
25,089
The circumcenter of a regular tetrahedron \( ABCD \) is \( O \). If \( E \) is the midpoint of \( BC \), what is the measure of the dihedral angle between \( A-BO-E \)?
\frac{2}{3}\pi
0
25,090
Given the functions $f(x)=x^{2}+px+q$ and $g(x)=x+\frac{1}{x^{2}}$ on the interval $[1,2]$, determine the maximum value of $f(x)$.
4 - \frac{5}{2} \sqrt[3]{2} + \sqrt[3]{4}
0
25,091
Calculate the sum of the first 4 terms of the geometric sequence $\{a_n\}$.
120
0
25,092
Let \( f : \mathbb{C} \to \mathbb{C} \) be defined by \( f(z) = z^2 - 2iz + 2 \). Determine the number of complex numbers \( z \) such that \( \text{Im}(z) > 0 \) and both the real and the imaginary parts of \( f(z) \) are integers within the range \(-5\) to \(5\).
143
0
25,093
A sequence \(a_1\), \(a_2\), \(\ldots\) of non-negative integers is defined by the rule \(a_{n+2}=|a_{n+1}-a_n|\) for \(n\geq1\). If \(a_1=1010\), \(a_2<1010\), and \(a_{2023}=0\), how many different values of \(a_2\) are possible?
399
0
25,094
Given quadrilateral ABCD, ∠A = 120∘, and ∠B and ∠D are right angles. Given AB = 13 and AD = 46, find the length of AC.
62
0
25,095
Find the smallest positive integer $k$ such that $1^2 + 2^2 + 3^2 + \ldots + k^2$ is a multiple of $150$.
100
0
25,096
Let $P$, $Q$, and $R$ be points on a circle of radius $12$. If $\angle PRQ = 110^\circ,$ find the circumference of the minor arc $PQ$. Express your answer in terms of $\pi$.
\frac{22}{3}\pi
0.78125
25,097
A merchant acquires goods at a discount of $30\%$ of the list price and intends to sell them with a $25\%$ profit margin after a $25\%$ discount on the marked price. Determine the required percentage of the original list price that the goods should be marked.
124\%
0
25,098
Let $M$ be a set of $99$ different rays with a common end point in a plane. It's known that two of those rays form an obtuse angle, which has no other rays of $M$ inside in. What is the maximum number of obtuse angles formed by two rays in $M$ ?
3267
0
25,099
How many positive integers \( n \) are there such that \( n \) is a multiple of 4, and the least common multiple of \( 4! \) and \( n \) equals 4 times the greatest common divisor of \( 8! \) and \( n \)?
12
3.90625