Unnamed: 0
int64
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40.3k
problem
stringlengths
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5.15k
ground_truth
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float64
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100
15,800
Calculate the integral \(\int_{0}^{\pi / 2} \frac{\sin^{3} x}{2 + \cos x} \, dx\).
3 \ln \left(\frac{2}{3}\right) + \frac{3}{2}
0.78125
15,801
Given a positive number \(r\) such that the set \(T=\left\{(x, y) \mid x, y \in \mathbf{R}\right.\) and \(\left.x^{2}+(y-7)^{2} \leqslant r^{2}\right\}\) is a subset of the set \(S=\{(x, y) \mid x, y \in \mathbf{R}\right.\) and for any \(\theta \in \mathbf{R}\), \(\cos 2\theta + x \cos \theta + y \geqslant 0\},\) deter...
4 \sqrt{2}
26.5625
15,802
In the acute triangle \( \triangle ABC \), the sides \( a, b, c \) are opposite to the angles \( \angle A, \angle B, \angle C \) respectively, and \( a, b, c \) form an arithmetic sequence. Also, \( \sin (A - C) = \frac{\sqrt{3}}{2} \). Find \( \sin (A + C) \).
\frac{\sqrt{39}}{8}
2.34375
15,803
Let \( x_{1}, x_{2}, x_{3}, x_{4} \) be non-negative real numbers satisfying the equation: \[ x_{1} + x_{2} + x_{3} + x_{4} = 1 \] Find the maximum value of \( \sum_{1 \leq i < j \leq 4}(x_{i} + x_{j}) \sqrt{x_{i} x_{j}} \), and determine the values of \( x_{1}, x_{2}, x_{3}, x_{4} \) that achieve this maximum value.
3/4
77.34375
15,804
Let the three sides of a triangle be integers \( l \), \( m \), and \( n \) with \( l > m > n \). It is known that \( \left\{\frac{3^l}{10^4}\right\} = \left\{\frac{3^m}{10^4}\right\} = \left\{\frac{3^n}{10^4}\right\} \), where \( \{x\} \) denotes the fractional part of \( x \). Determine the minimum value of the perim...
3003
1.5625
15,805
For each pair of real numbers \((x, y)\) with \(0 \leq x \leq y \leq 1\), consider the set \[ A = \{ x y, x y - x - y + 1, x + y - 2 x y \}. \] Let the maximum value of the elements in set \(A\) be \(M(x, y)\). Find the minimum value of \(M(x, y)\).
4/9
53.90625
15,806
2001 coins, each valued at 1, 2, or 3, are arranged in a row. The coins are placed such that: - Between any two coins of value 1, there is at least one other coin. - Between any two coins of value 2, there are at least two other coins. - Between any two coins of value 3, there are at least three other coins. What is t...
501
25
15,807
The steamboat "Rarity" travels for three hours at a constant speed after leaving the city, then drifts with the current for an hour, then travels for three hours at the same speed, and so on. If the steamboat starts its journey in city A and goes to city B, it takes it 10 hours. If it starts in city B and goes to city ...
60
13.28125
15,808
Given that \( p \) is a prime number and \( r \) is the remainder when \( p \) is divided by 210, if \( r \) is a composite number that can be expressed as the sum of two perfect squares, find \( r \).
169
4.6875
15,809
How many positive integers less than 2019 are divisible by either 18 or 21, but not both?
176
91.40625
15,810
A collector has \( N \) precious stones. If he takes away the three heaviest stones, then the total weight of the stones decreases by \( 35\% \). From the remaining stones, if he takes away the three lightest stones, the total weight further decreases by \( \frac{5}{13} \). Find \( N \).
10
21.09375
15,811
Two people, A and B, play a "guess the number" game using a fair six-sided die (the faces of the die are numbered $1, 2, \cdots, 6$). Each person independently thinks of a number on the die, denoted as $a$ and $b$. If $|a - b| \leqslant 1$, they are said to be "in sync." What is the probability that A and B are in sync...
4/9
100
15,812
There are exactly 120 ways to color five cells in a $5 \times 5$ grid such that exactly one cell in each row and each column is colored. There are exactly 96 ways to color five cells in a $5 \times 5$ grid without the corner cell, such that exactly one cell in each row and each column is colored. How many ways are th...
78
60.15625
15,813
Find the number of integers from 1 to 1000 inclusive that give the same remainder when divided by 11 and by 12.
87
1.5625
15,814
Given a triangle \( ACE \) with a point \( B \) on segment \( AC \) and a point \( D \) on segment \( CE \) such that \( BD \) is parallel to \( AE \). A point \( Y \) is chosen on segment \( AE \), and segment \( CY \) is drawn, intersecting \( BD \) at point \( X \). If \( CX = 5 \) and \( XY = 3 \), what is the rati...
39/25
83.59375
15,815
The function \( f(x) = \max \left\{\sin x, \cos x, \frac{\sin x + \cos x}{\sqrt{2}}\right\} \) (for \( x \in \mathbb{R} \)) has a maximum value and a minimum value. Find the sum of these maximum and minimum values.
1 - \frac{\sqrt{2}}{2}
7.8125
15,816
How many ways are there to list the numbers 1 to 10 in some order such that every number is either greater or smaller than all the numbers before it?
512
6.25
15,817
During breaks, schoolchildren played table tennis. Any two schoolchildren played no more than one game against each other. At the end of the week, it turned out that Petya played half, Kolya - a third, and Vasya - one fifth of the total number of games played during the week. What could be the total number of games pla...
30
39.84375
15,818
Given that the interior angles \(A, B, C\) of triangle \(\triangle ABC\) are opposite to the sides \(a, b, c\) respectively, and that \(A - C = \frac{\pi}{2}\), and \(a, b, c\) form an arithmetic sequence, find the value of \(\cos B\).
\frac{3}{4}
10.9375
15,819
Let \( A = \{ x \mid 5x - a \leqslant 0 \} \) and \( B = \{ x \mid 6x - b > 0 \} \), where \( a, b \in \mathbb{N}_+ \). If \( A \cap B \cap \mathbb{N} = \{ 2, 3, 4 \} \), find the number of integer pairs \((a, b)\).
30
46.09375
15,820
Calculate the definite integral: $$ \int_{0}^{\pi} 2^{4} \cdot \sin ^{8} x \, dx $$
\frac{35\pi}{8}
85.9375
15,821
A rectangular piece of paper with a length of 20 cm and a width of 12 cm is folded along its diagonal (refer to the diagram). What is the perimeter of the shaded region formed?
64
41.40625
15,822
One day, Xiao Ming took 100 yuan to go shopping. In the first store, he bought several items of product A. In the second store, he bought several items of product B. In the third store, he bought several items of product C. In the fourth store, he bought several items of product D. In the fifth store, he bought several...
28
0
15,823
How many natural numbers with up to six digits contain the digit 1?
468559
47.65625
15,824
A triangle has sides of lengths 20 and 19. If the triangle is not acute, how many possible integer lengths can the third side have?
16
27.34375
15,825
$S$ is a subset of the set $\{1, 2, \cdots, 2023\}$, such that the sum of the squares of any two elements is not a multiple of 9. What is the maximum value of $|S|$? (Here, $|S|$ represents the number of elements in $S$.)
1350
3.90625
15,826
Inside the cube \( ABCD A_1 B_1 C_1 D_1 \) is located the center \( O \) of a sphere with a radius of 10. The sphere intersects the face \( A A_1 D_1 D \) in a circle with a radius of 1, the face \( A_1 B_1 C_1 D_1 \) in a circle with a radius of 1, and the face \( C D D_1 C_1 \) in a circle with a radius of 3. Find th...
17
41.40625
15,827
How can you weigh 1 kg of grain on a balance scale using two weights, one weighing 300 g and the other 650 g?
1000
29.6875
15,828
All vertices of a regular tetrahedron \( A B C D \) are located on one side of the plane \( \alpha \). It turns out that the projections of the vertices of the tetrahedron onto the plane \( \alpha \) are the vertices of a certain square. Find the value of \(A B^{2}\), given that the distances from points \( A \) and \(...
32
6.25
15,829
Let \( p(x) = x^4 + ax^3 + bx^2 + cx + d \), where \( a, b, c, \) and \( d \) are constants. Given \( p(1) = 1993 \), \( p(2) = 3986 \), \( p(3) = 5979 \), find \( \frac{1}{4} [p(11) + p(-7)] \).
5233
47.65625
15,830
A necklace consists of 80 beads of red, blue, and green colors. It is known that in any segment of the necklace between two blue beads, there is at least one red bead, and in any segment of the necklace between two red beads, there is at least one green bead. What is the minimum number of green beads in this necklace? ...
27
37.5
15,831
Petya cut an 8x8 square along the borders of the cells into parts of equal perimeter. It turned out that not all parts are equal. What is the maximum possible number of parts he could get?
21
0
15,832
Given that $\angle BAC = 90^{\circ}$ and the quadrilateral $ADEF$ is a square with side length 1, find the maximum value of $\frac{1}{AB} + \frac{1}{BC} + \frac{1}{CA}$.
2 + \frac{\sqrt{2}}{2}
7.03125
15,833
Let \( x \) be a positive integer, and write \( a = \left\lfloor \log_{10} x \right\rfloor \) and \( b = \left\lfloor \log_{10} \frac{100}{x} \right\rfloor \). Here \( \lfloor c \rfloor \) denotes the greatest integer less than or equal to \( c \). Find the largest possible value of \( 2a^2 - 3b^2 \).
24
0.78125
15,834
In a box, there are 3 red, 4 gold, and 5 silver stars. Stars are randomly drawn one by one from the box and placed on a Christmas tree. What is the probability that a red star is placed on the top of the tree, no more red stars are on the tree, and there are exactly 3 gold stars on the tree, if a total of 6 stars are ...
5/231
4.6875
15,835
In the year 2009, there is a property that rearranging the digits of the number 2009 cannot yield a smaller four-digit number (numbers do not start with zero). In what subsequent year does this property first repeat again?
2022
35.15625
15,836
Given \( x, y, z \in (0, +\infty) \) and \(\frac{x^2}{1+x^2} + \frac{y^2}{1+y^2} + \frac{z^2}{1+z^2} = 2 \), find the maximum value of \(\frac{x}{1+x^2} + \frac{y}{1+y^2} + \frac{z}{1+z^2}\).
\sqrt{2}
54.6875
15,837
On the sides of triangle \(ABC\), points were marked: 10 on side \(AB\), 11 on side \(BC\), and 12 on side \(AC\). None of the vertices of the triangle were marked. How many triangles with vertices at the marked points exist?
4951
2.34375
15,838
The fare in Moscow with the "Troika" card in 2016 is 32 rubles for one trip on the metro and 31 rubles for one trip on ground transportation. What is the minimum total number of trips that can be made at these rates, spending exactly 5000 rubles?
157
27.34375
15,839
The value of the expression \(10 - 10.5 \div [5.2 \times 14.6 - (9.2 \times 5.2 + 5.4 \times 3.7 - 4.6 \times 1.5)]\) is
9.3
51.5625
15,840
In the Cartesian coordinate system \( xOy \), the area of the region corresponding to the set of points \( K = \{(x, y) \mid (|x| + |3y| - 6)(|3x| + |y| - 6) \leq 0 \} \) is ________.
24
13.28125
15,841
Inside triangle \(ABC\), a point \(O\) is chosen such that \(\angle ABO = \angle CAO\), \(\angle BAO = \angle BCO\), and \(\angle BOC = 90^{\circ}\). Find the ratio \(AC : OC\).
\sqrt{2}
14.84375
15,842
On the board, the number 27 is written. Every minute, the number is erased from the board and replaced with the product of its digits increased by 12. For example, after one minute, the number on the board will be $2 \cdot 7 + 12 = 26$. What number will be on the board after an hour?
14
90.625
15,843
Tanya wrote a certain two-digit number on a piece of paper; to Sveta, who was sitting opposite her, the written number appeared different and was 75 less. What number did Tanya write?
91
29.6875
15,844
What is the maximum number of checkers that can be placed on a $6 \times 6$ board such that no three checkers (specifically, the centers of the cells they occupy) are on the same line (regardless of the angle of inclination)?
12
40.625
15,845
Let \( z \) be a complex number with a modulus of 1. Then the maximum value of \(\left|\frac{z+\mathrm{i}}{z+2}\right|\) is \(\ \ \ \ \ \ \).
\frac{2\sqrt{5}}{3}
0
15,846
A car left the city for the village, and simultaneously, a cyclist left the village for the city. When the car and the cyclist met, the car immediately turned around and went back to the city. As a result, the cyclist arrived in the city 35 minutes later than the car. How many minutes did the cyclist spend on the entir...
55
15.625
15,847
A polygon is said to be friendly if it is regular and it also has angles that, when measured in degrees, are either integers or half-integers (i.e., have a decimal part of exactly 0.5). How many different friendly polygons are there?
28
34.375
15,848
In how many ways can the number 1024 be factored into three natural factors such that the first factor is a multiple of the second, and the second is a multiple of the third?
14
57.8125
15,849
Two people are flipping a coin: one flipped it 10 times, and the other flipped it 11 times. Find the probability that the second person got heads more times than the first person.
\frac{1}{2}
61.71875
15,850
Given the ellipse $\frac{x^{2}}{4}+\frac{y^{2}}{3}=1$ with left and right foci $F_{1}$ and $F_{2}$ respectively, draw a line $l$ through the right focus that intersects the ellipse at points $P$ and $Q$. Find the maximum area of the inscribed circle of triangle $F_{1} PQ$.
\frac{9 \pi}{16}
14.0625
15,851
There are two positive integers \( A \) and \( B \). The sum of the digits of \( A \) is 19, and the sum of the digits of \( B \) is 20. When the two numbers are added together, there are two carries. What is the sum of the digits of \( (A+B) \)?
21
89.0625
15,852
The common ratio of the geometric sequence \( a + \log_{2} 3, a + \log_{4} 3, a + \log_{8} 3 \) is?
\frac{1}{3}
35.9375
15,853
The school organized a picnic with several attendees. The school prepared many empty plates. Each attendee who arrives will count the empty plates and then take one plate for food (no one can take more than one plate). The first attendee will count all the empty plates, the second will count one fewer, and so on. The l...
1006
65.625
15,854
Regular decagon (10-sided polygon) \(A B C D E F G H I J\) has an area of 2017 square units. Determine the area (in square units) of the rectangle \(C D H I\).
806.8
50
15,855
Out of sixteen Easter eggs, three are red. Ten eggs were placed in a larger box and six in a smaller box at random. What is the probability that both boxes contain at least one red egg?
3/4
21.875
15,856
Given the point \( P \) lies in the plane of the right triangle \( \triangle ABC \) with \( \angle BAC = 90^\circ \), and \( \angle CAP \) is an acute angle. Also given are the conditions: \[ |\overrightarrow{AP}| = 2, \quad \overrightarrow{AP} \cdot \overrightarrow{AC} = 2, \quad \overrightarrow{AP} \cdot \overrightar...
\frac{\sqrt{2}}{2}
3.125
15,857
In the plane Cartesian coordinate system \(xOy\), the set of points $$ \begin{aligned} K= & \{(x, y) \mid(|x|+|3 y|-6) \cdot \\ & (|3 x|+|y|-6) \leqslant 0\} \end{aligned} $$ corresponds to an area in the plane with the measurement of ______.
24
23.4375
15,858
Each of two teams, Team A and Team B, sends 7 players in a predetermined order to participate in a Go contest. The players from both teams compete sequentially starting with Player 1 from each team. The loser of each match is eliminated, and the winner continues to compete with the next player from the opposing team. T...
3432
46.875
15,859
At around 8 o'clock in the morning, two cars left the fertilizer plant one after another, heading toward Happy Village. Both cars travel at a speed of 60 kilometers per hour. At 8:32, the distance the first car had traveled from the fertilizer plant was three times the distance traveled by the second car. At 8:39, the ...
8:11
10.9375
15,860
How many natural five-digit numbers have the product of their digits equal to 2000?
30
63.28125
15,861
Given that \(\frac{x+y}{x-y}+\frac{x-y}{x+y}=3\). Find the value of the expression \(\frac{x^{2}+y^{2}}{x^{2}-y^{2}}+\frac{x^{2}-y^{2}}{x^{2}+y^{2}}\).
13/6
31.25
15,862
Cubes. As is known, the whole space can be filled with equal cubes. At each vertex, eight cubes will converge. Therefore, by appropriately truncating the vertices of the cubes and joining the adjacent truncated parts into a single body, it is possible to fill the space with regular octahedra and the remaining bodies fr...
\frac{1}{6}
16.40625
15,863
Pi Pi Lu wrote a 2020-digit number: \( 5368 \cdots \cdots \). If any four-digit number taken randomly from this multi-digit number is divisible by 11, what is the sum of the digits of this multi-digit number?
11110
70.3125
15,864
A typesetter scattered part of a set - a set of a five-digit number that is a perfect square, written with the digits $1, 2, 5, 5,$ and $6$. Find all such five-digit numbers.
15625
50
15,865
A child gave Carlson 111 candies. They ate some of them right away, 45% of the remaining candies went to Carlson for lunch, and a third of the candies left after lunch were found by Freken Bok during cleaning. How many candies did she find?
11
17.96875
15,866
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
30.46875
15,867
Calculate \( \frac{2}{1} \times \frac{2}{3} \times \frac{4}{3} \times \frac{4}{5} \times \frac{6}{5} \times \frac{6}{7} \times \frac{8}{7} \). Express the answer in decimal form, accurate to two decimal places.
1.67
49.21875
15,868
Given $\boldsymbol{a} = (\cos \alpha, \sin \alpha)$ and $\boldsymbol{b} = (\cos \beta, \sin \beta)$, the relationship between $\boldsymbol{a}$ and $\boldsymbol{b}$ is given by $|k \boldsymbol{a} + \boldsymbol{b}| - \sqrt{3}|\boldsymbol{a} - k \boldsymbol{b}|$, where $k > 0$. Find the minimum value of $\boldsymbol{a} \...
\frac{1}{2}
46.09375
15,869
On a sheet of graph paper, two rectangles are outlined. The first rectangle has a vertical side shorter than the horizontal side, and for the second rectangle, the opposite is true. Find the maximum possible area of their intersection if the first rectangle contains 2015 cells and the second one contains 2016 cells.
1302
6.25
15,870
Inside a right angle with vertex \(O\), there is a triangle \(OAB\) with a right angle at \(A\). The height of the triangle \(OAB\), dropped to the hypotenuse, is extended past point \(A\) to intersect with the side of the angle at point \(M\). The distances from points \(M\) and \(B\) to the other side of the angle ar...
\sqrt{2}
3.90625
15,871
Calculate: \( 4\left(\sin ^{3} \frac{49 \pi}{48} \cos \frac{49 \pi}{16} + \cos ^{3} \frac{49 \pi}{48} \sin \frac{49 \pi}{16}\right) \cos \frac{49 \pi}{12} \).
0.75
0
15,872
A box contains one hundred multicolored balls: 28 red, 20 green, 13 yellow, 19 blue, 11 white, and 9 black. What is the minimum number of balls that must be drawn from the box, without looking, to ensure that at least 15 balls of one color are among them?
76
79.6875
15,873
Find the smallest natural number that is greater than the sum of its digits by 1755.
1770
83.59375
15,874
Find the measure of angle \( B \widehat{A} D \), given that \( D \widehat{A C}=39^{\circ} \), \( A B = A C \), and \( A D = B D \).
47
8.59375
15,875
Let squares of one kind have a side of \(a\) units, another kind have a side of \(b\) units, and the original square have a side of \(c\) units. Then the area of the original square is given by \(c^{2}=n a^{2}+n b^{2}\). Numbers satisfying this equation can be obtained by multiplying the equality \(5^{2}=4^{2}+3^{2}\...
15
34.375
15,876
Gabor wanted to design a maze. He took a piece of grid paper and marked out a large square on it. From then on, and in the following steps, he always followed the lines of the grid, moving from grid point to grid point. Then he drew some lines within the square, totaling 400 units in length. These lines became the wall...
21
53.90625
15,877
In a taxi, one passenger can sit in the front and three in the back. In how many ways can the four passengers be seated if one of them wants to sit by the window?
12
16.40625
15,878
What is the largest number of white and black chips that can be placed on a chessboard so that on each horizontal and each vertical, the number of white chips is exactly twice the number of black chips?
48
48.4375
15,879
Given a cube $A B C D-A_{1} B_{1} C_{1} D_{1}$ with edge length $1$, let $P$ be a moving point on the space diagonal $B C_{1}$ and $Q$ be a moving point on the base $A B C D$. Find the minimum value of $D_{1} P + P Q$.
1 + \frac{\sqrt{2}}{2}
0
15,880
Find the smallest two-digit number \( N \) such that the sum of digits of \( 10^N - N \) is divisible by 170.
20
99.21875
15,881
An odd six-digit number is called "just cool" if it consists of digits that are prime numbers, and no two identical digits are adjacent. How many "just cool" numbers exist?
729
51.5625
15,882
Given that \( I \) is the incenter of \( \triangle ABC \) and \( 5 \overrightarrow{IA} = 4(\overrightarrow{BI} + \overrightarrow{CI}) \). Let \( R \) and \( r \) be the radii of the circumcircle and the incircle of \( \triangle ABC \) respectively. If \( r = 15 \), then find \( R \).
32
3.90625
15,883
We call a number antitriangular if it can be expressed in the form \(\frac{2}{n(n+1)}\) for some natural number \(n\). For how many numbers \(k\) (where \(1000 \leq k \leq 2000\)) can the number 1 be expressed as the sum of \(k\) antitriangular numbers (not necessarily distinct)?
1001
21.875
15,884
Construct spheres that are tangent to 4 given spheres. If we accept the point (a sphere with zero radius) and the plane (a sphere with infinite radius) as special cases, how many such generalized spatial Apollonian problems exist?
15
28.90625
15,885
One mole of an ideal monatomic gas is first heated isobarically, performing 10 Joules of work. Then it is heated isothermally, receiving the same amount of heat as in the first case. How much work does the gas perform (in Joules) in the second case?
25
56.25
15,886
For how many integers \( n \) is \(\frac{2n^3 - 12n^2 - 2n + 12}{n^2 + 5n - 6}\) equal to an integer?
32
4.6875
15,887
For the numbers \(1000^{2}, 1001^{2}, 1002^{2}, \ldots\), the last two digits are discarded. How many of the first terms in the resulting sequence form an arithmetic progression?
10
28.90625
15,888
Gru and the Minions plan to make money through cryptocurrency mining. They chose Ethereum as one of the most stable and promising currencies. They bought a system unit for 9499 rubles and two graphics cards for 31431 rubles each. The power consumption of the system unit is 120 W, and for each graphics card, it is 125 W...
165
19.53125
15,889
Points \( A, B, C \), and \( D \) are located on a line such that \( AB = BC = CD \). Segments \( AB \), \( BC \), and \( CD \) serve as diameters of circles. From point \( A \), a tangent line \( l \) is drawn to the circle with diameter \( CD \). Find the ratio of the chords cut on line \( l \) by the circles with di...
\sqrt{6}: 2
0
15,890
In rectangle \(ABCD\), \(AB = 20 \, \text{cm}\) and \(BC = 10 \, \text{cm}\). Points \(M\) and \(N\) are taken on \(AC\) and \(AB\), respectively, such that the value of \(BM + MN\) is minimized. Find this minimum value.
16
2.34375
15,891
If \(\sqrt{9-8 \sin 50^{\circ}}=a+b \csc 50^{\circ}\) where \(a, b\) are integers, find \(ab\).
-3
13.28125
15,892
Given a real number \(a\), and for any \(k \in [-1, 1]\), when \(x \in (0, 6]\), the inequality \(6 \ln x + x^2 - 8x + a \leq kx\) always holds. Determine the maximum value of \(a\).
6 - 6 \ln 6
11.71875
15,893
In a singing contest, a Rooster, a Crow, and a Cuckoo were contestants. Each jury member voted for one of the three contestants. The Woodpecker tallied that there were 59 judges, and that the sum of votes for the Rooster and the Crow was 15, the sum of votes for the Crow and the Cuckoo was 18, and the sum of votes for ...
13
1.5625
15,894
Given that four integers \( a, b, c, d \) are all even numbers, and \( 0 < a < b < c < d \), with \( d - a = 90 \). If \( a, b, c \) form an arithmetic sequence and \( b, c, d \) form a geometric sequence, then find the value of \( a + b + c + d \).
194
26.5625
15,895
Let \( S = \{1, 2, \cdots, 2009\} \). \( A \) is a 3-element subset of \( S \) such that all elements in \( A \) form an arithmetic sequence. How many such 3-element subsets \( A \) are there?
1008016
85.15625
15,896
Two players, \(A\) and \(B\), play rock-paper-scissors continuously until player \(A\) wins 2 consecutive games. Suppose each player is equally likely to use each hand sign in every game. What is the expected number of games they will play?
12
58.59375
15,897
Given \(0<\theta<\pi\), a complex number \(z_{1}=1-\cos \theta+i \sin \theta\) and \(z_{2}=a^{2}+a i\), where \(a \in \mathbb{R}\), it is known that \(z_{1} z_{2}\) is a pure imaginary number, and \(\bar{a}=z_{1}^{2}+z_{2}^{2}-2 z_{1} z_{2}\). Determine the value of \(\theta\) when \(\bar{a}\) is a negative real number...
\frac{\pi}{2}
32.03125
15,898
Team A and Team B each have 7 players who compete in a predetermined order in a Go competition. Initially, Player 1 from each team competes. The loser is eliminated, and the winner competes next against the loser's team Player 2, and so on, until all players from one team are eliminated. The remaining team wins. How ma...
3432
63.28125
15,899
By solving the inequality \(\sqrt{x^{2}+3 x-54}-\sqrt{x^{2}+27 x+162}<8 \sqrt{\frac{x-6}{x+9}}\), find the sum of its integer solutions within the interval \([-25, 25]\).
310
0