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Francine drives 140km to work each day. If she does not go to work 3 days every week, find the total distance she drives to work for 4 weeks in kilometers.
There are 7 days in a week, so if he doesn't go to work for 3 days, he goes 7-3 = <<7-3=4>>4 days every week He travels 140km each day for a weekly total of 140*4 = <<140*4=560>>560km In 4 weeks he will travel a total of 4*560 = <<4*560=2240>>2240km #### 2240
Simplify $$\sqrt{6+4\sqrt2}+\sqrt{6-4\sqrt2}.$$
4
An equiangular hexagon has side lengths $1,1, a, 1,1, a$ in that order. Given that there exists a circle that intersects the hexagon at 12 distinct points, we have $M<a<N$ for some real numbers $M$ and $N$. Determine the minimum possible value of the ratio $\frac{N}{M}$.
\frac{3 \sqrt{3}+3}{2}
A single line is worth 1000 points. A tetris is worth 8 times that much. Tim scored 6 singles and 4 tetrises. How many points did he score?
A tetris is worth 8*1000=<<8*1000=8000>>8000 points So he scored 4*8000=<<4*8000=32000>>32000 points from tetrises He also scores 6*1000=<<6*1000=6000>>6000 points from singles So in total he scores 32000+6000=<<32000+6000=38000>>38,000 points #### 38000
Let $h(4x-1) = 2x + 7$. For what value of $x$ is $h(x) = x$?
15
Of the 60 students in the drama club, 36 take mathematics, 27 take physics and 20 students take both mathematics and physics. How many drama club students take neither mathematics nor physics?
17
The ratio of the measures of the acute angles of a right triangle is $8:1$. In degrees, what is the measure of the largest angle of the triangle?
90^\circ
If the orthocenter of \( \triangle OAB \) is exactly the focus of the parabola \( y^2 = 4x \), where \( O \) is the origin and points \( A \) and \( B \) lie on the parabola, then the area of \( \triangle OAB \) is equal to ____.
10\sqrt{5}
Indecisive Andy starts out at the midpoint of the 1-unit-long segment $\overline{H T}$. He flips 2010 coins. On each flip, if the coin is heads, he moves halfway towards endpoint $H$, and if the coin is tails, he moves halfway towards endpoint $T$. After his 2010 moves, what is the expected distance between Andy and the midpoint of $\overline{H T}$ ?
\frac{1}{4}
How many paths are there from the starting point $C$ to the end point $D$, if every step must be up or to the right in a grid of 8 columns and 7 rows?
6435
What is the result of the correct calculation for the product $0.08 \times 3.25$?
0.26
The sum of the squares of four consecutive positive integers is 9340. What is the sum of the cubes of these four integers?
457064
Let's call a number palindromic if it reads the same left to right as it does right to left. For example, the number 12321 is palindromic. a) Write down any five-digit palindromic number that is divisible by 5. b) How many five-digit palindromic numbers are there that are divisible by 5?
100
$ABCD$ is a rectangle; $P$ and $Q$ are the mid-points of $AB$ and $BC$ respectively. $AQ$ and $CP$ meet at $R$. If $AC = 6$ and $\angle ARC = 150^{\circ}$, find the area of $ABCD$.
8\sqrt{3}
Given a square side of length $s$. On a diagonal as base a triangle with three unequal sides is constructed so that its area equals that of the square. The length of the altitude drawn to the base is:
$s\sqrt{2}$
Green Valley School has 120 students enrolled, consisting of 70 boys and 50 girls. If $\frac{1}{7}$ of the boys and $\frac{1}{5}$ of the girls are absent on a particular day, what percent of the total student population is absent?
16.67\%
Given the equations $z^2 = 1 + 3\sqrt{10}i$ and $z^2 = 2 - 2\sqrt{2}i$, where $i = \sqrt{-1}$, find the vertices formed by the solutions of these equations on the complex plane and compute the area of the quadrilateral they form. A) $17\sqrt{6} - 2\sqrt{2}$ B) $18\sqrt{6} - 3\sqrt{2}$ C) $19\sqrt{6} - 2\sqrt{2}$ D) $20\sqrt{6} - 2\sqrt{2}$
19\sqrt{6} - 2\sqrt{2}
Given \\(\sin \theta + \cos \theta = \frac{3}{4}\\), where \\(\theta\\) is an angle of a triangle, the value of \\(\sin \theta - \cos \theta\\) is \_\_\_\_\_.
\frac{\sqrt{23}}{4}
Find the matrix that corresponds to a dilation centered at the origin with scale factor $-3.$
\begin{pmatrix} -3 & 0 \\ 0 & -3 \end{pmatrix}
There are 60 empty boxes $B_1,\ldots,B_{60}$ in a row on a table and an unlimited supply of pebbles. Given a positive integer $n$, Alice and Bob play the following game. In the first round, Alice takes $n$ pebbles and distributes them into the 60 boxes as she wishes. Each subsequent round consists of two steps: (a) Bob chooses an integer $k$ with $1\leq k\leq 59$ and splits the boxes into the two groups $B_1,\ldots,B_k$ and $B_{k+1},\ldots,B_{60}$. (b) Alice picks one of these two groups, adds one pebble to each box in that group, and removes one pebble from each box in the other group. Bob wins if, at the end of any round, some box contains no pebbles. Find the smallest $n$ such that Alice can prevent Bob from winning. [i]Czech Republic[/i]
960
A cuckoo clock chimes "cuckoo" as many times as the hour indicated by the hour hand (e.g., at 19:00, it chimes 7 times). One morning, Maxim approached the clock at 9:05 and started turning the minute hand until the clock advanced by 7 hours. How many times did the clock chime "cuckoo" during this period?
43
Find the equation whose graph is a parabola with vertex $(2,4)$, vertical axis of symmetry, and contains the point $(1,1)$. Express your answer in the form "$ax^2+bx+c$".
-3x^2+12x-8
Let $\alpha$ and $\beta$ be complex numbers such that $\alpha + \beta$ and $i(\alpha - 2 \beta)$ are both positive real numbers. If $\beta = 3 + 2i,$ compute $\alpha.$
6 - 2i
Lily got a new puppy for her birthday. She was responsible for feeding the puppy 1/4 cup of food three times a day for two weeks starting tomorrow. For the following 2 weeks, Lily will feed him 1/2 cup of food twice a day. She has fed him 1/2 cup of food today. Including today, how much food will the puppy eat over the next 4 weeks?
1 week has 7 days so 2 weeks will have 2*7 = <<7*2=14>>14 days The puppy will eat 1/4c three times a day so .25*3= <<.25*3=.75>>.75 cups per day The puppy will eat .75 cups of food a day for 14 days for a total of .75*14 =<<.75*14=10.5>>10.5 cups The puppy will then eat `.5 cup of food twice a day so .5*2 = <<.5*2=1>>1 cup per day The puppy will eat 1 cup of food a day for 14 days for a total of 1*14 = <<1*14=14>>14 cups per day She has already fed him .5 cup of food and he will eat 10.5 cups and another 14 cups for a total of .5+10.5+14 = <<.5+10.5+14=25>>25 cups of food #### 25
Given the positive sequence $\{a_n\}$, where $a_1=2$, $a_2=1$, and $\frac {a_{n-1}-a_{n}}{a_{n}a_{n-1}}= \frac {a_{n}-a_{n+1}}{a_{n}a_{n+1}}(n\geqslant 2)$, find the value of the 2016th term of this sequence.
\frac{1}{1008}
Given \( z \in \mathbf{C} \) and \( z^{7} = 1 \) (where \( z \neq 1 \)), find the value of \( \cos \alpha + \cos 2 \alpha + \cos 4 \alpha \), where \(\alpha\) is the argument of \(z\).
-\frac{1}{2}
The real numbers $c, b, a$ form an arithmetic sequence with $a \geq b \geq c \geq 0$. The quadratic $ax^2+bx+c$ has exactly one root. What is this root?
-2-\sqrt{3}
Find the equation of the line that passes through the intersection of the lines $2x+3y+5=0$ and $2x+5y+7=0$, and is parallel to the line $x+3y=0$. Also, calculate the distance between these two parallel lines.
\frac{2\sqrt{10}}{5}
The price of an item is decreased by 20%. To bring it back to its original value and then increase it by an additional 10%, the price after restoration must be increased by what percentage.
37.5\%
Given that a, b, and c are the sides opposite to angles A, B, and C respectively in triangle ABC, and c = 2, sinC(cosB - $\sqrt{3}$sinB) = sinA. (1) Find the measure of angle C; (2) If cosA = $\frac{2\sqrt{2}}{3}$, find the length of side b.
\frac{4\sqrt{2} - 2\sqrt{3}}{3}
Two cyclists, $k$ miles apart, and starting at the same time, would be together in $r$ hours if they traveled in the same direction, but would pass each other in $t$ hours if they traveled in opposite directions. The ratio of the speed of the faster cyclist to that of the slower is:
\frac {r + t}{r - t}
Given cos(π/4 - α) = 3/5 and sin(5π/4 + β) = -12/13, where α ∈ (π/4, 3π/4) and β ∈ (0, π/4), find tan(α)/tan(β).
-17
Given vectors $\overrightarrow{a}=(2\cos\omega x,-2)$ and $\overrightarrow{b}=(\sqrt{3}\sin\omega x+\cos\omega x,1)$, where $\omega\ \ \gt 0$, and the function $f(x)=\overrightarrow{a}\cdot\overrightarrow{b}+1$. The distance between two adjacent symmetric centers of the graph of $f(x)$ is $\frac{\pi}{2}$. $(1)$ Find $\omega$; $(2)$ Given $a$, $b$, $c$ are the opposite sides of the three internal angles $A$, $B$, $C$ of scalene triangle $\triangle ABC$, and $f(A)=f(B)=\sqrt{3}$, $a=\sqrt{2}$, find the area of $\triangle ABC$.
\frac{3-\sqrt{3}}{4}
Point $(x,y)$ is randomly picked from the rectangular region with vertices at $(0,0),(2008,0),(2008,2009),$ and $(0,2009)$. What is the probability that $x > 2y$? Express your answer as a common fraction.
\frac{502}{2009}
What is the value of $n$ such that $10^n = 10^{-5}\times \sqrt{\frac{10^{73}}{0.001}}$?
33
Find the largest value of $n$ such that $5x^2+nx+48$ can be factored as the product of two linear factors with integer coefficients.
241
The perimeter of a rectangle is 56 meters. The ratio of its length to its width is 4:3. What is the length in meters of a diagonal of the rectangle?
20
Urn A contains 4 white balls and 2 red balls. Urn B contains 3 red balls and 3 black balls. An urn is randomly selected, and then a ball inside of that urn is removed. We then repeat the process of selecting an urn and drawing out a ball, without returning the first ball. What is the probability that the first ball drawn was red, given that the second ball drawn was black?
7/15
Four fair eight-sided dice (with faces showing 1 to 8) are rolled. What is the probability that the sum of the numbers on the top faces equals 32?
\frac{1}{4096}
On the hypotenuse \( AB \) of a right triangle \( ABC \), square \( ABDE \) is constructed externally with \( AC=2 \) and \( BC=5 \). In what ratio does the angle bisector of angle \( C \) divide side \( DE \)?
2 : 5
In this addition problem, each letter stands for a different digit. $\begin{array}{cccc}&T & W & O\\ +&T & W & O\\ \hline F& O & U & R\end{array}$ If T = 7 and the letter O represents an even number, what is the only possible value for W?
3
Find $\begin{pmatrix} 3 & 0 \\ 1 & 2 \end{pmatrix} + \begin{pmatrix} -5 & -7 \\ 4 & -9 \end{pmatrix}.$
\begin{pmatrix} -2 & -7 \\ 5 & -7 \end{pmatrix}
Given the function $f(x)=x+\sqrt{1-x}$, determine the minimum value of $f(x)$.
\frac{5}{4}
The archipelago consists of $N \geqslant 7$ islands. Any two islands are connected by no more than one bridge. It is known that no more than 5 bridges lead from each island and that among any 7 islands, there are always two that are connected by a bridge. What is the maximum possible value of $N$?
36
The sum of two numbers is $10$; their product is $20$. The sum of their reciprocals is:
\frac{1}{2}
Hooligan Vasily tore out an entire chapter from a book, with the first page numbered 231, and the number of the last page consisted of the same digits. How many sheets did Vasily tear out of the book?
41
Let $a,$ $b,$ $c$ be the roots of $x^3 + px + q = 0.$ Express \[\begin{vmatrix} 1 + a & 1 & 1 \\ 1 & 1 + b & 1 \\ 1 & 1 & 1 + c \end{vmatrix}\]in terms of $p$ and $q.$
p - q
How many of the natural numbers from 1 to 1000, inclusive, contain the digit 5 at least once?
270
A box contains $3$ cards labeled with $1$, $2$, and $3$ respectively. A card is randomly drawn from the box, its number recorded, and then returned to the box. This process is repeated. The probability that at least one of the numbers drawn is even is _______.
\frac{5}{9}
Let $f$ be defined by \[f(x) = \left\{ \begin{array}{cl} 2-x & \text{ if } x \leq 1, \\ 2x-x^2 & \text{ if } x>1. \end{array} \right.\]Calculate $f^{-1}(-3)+f^{-1}(0)+f^{-1}(3)$.
4
How many different 8-digit positive integers exist if the digits from the second to the eighth can only be 0, 1, 2, 3, or 4?
703125
Given that $0 < \alpha < \frac{\pi}{2}$ and $0 < \beta < \frac{\pi}{2}$, if $\sin\left(\frac{\pi}{3}-\alpha\right) = \frac{3}{5}$ and $\cos\left(\frac{\beta}{2} - \frac{\pi}{3}\right) = \frac{2\sqrt{5}}{5}$, (I) find the value of $\sin \alpha$; (II) find the value of $\cos\left(\frac{\beta}{2} - \alpha\right)$.
\frac{11\sqrt{5}}{25}
There is a sphere with a radius of $\frac{\sqrt{3}}{2}$, on which 4 points $A, B, C, D$ form a regular tetrahedron. What is the maximum distance from the center of the sphere to the faces of the regular tetrahedron $ABCD$?
\frac{\sqrt{3}}{6}
While practising for his upcoming math exams, Hayes realised that the area of a circle he had just solved was equal to the perimeter of a square he had solved in the previous problem. If the area of the circle was 100, what's the length of one side of the square?
Let's say the side of a square is s.To get the perimeter of a square, you add all the sides, which is s+s+s+s = 100 Therefore, 4s=<<100=100>>100 Therefore one side of the square is s =100/4 = <<100/4=25>>25 #### 25
A 10-cm-by-10-cm square is partitioned such that points $A$ and $B$ are on two opposite sides of the square at one-third and two-thirds the length of the sides, respectively. What is the area of the new shaded region formed by connecting points $A$, $B$, and their reflections across the square's diagonal? [asy] draw((0,0)--(15,0)); draw((15,0)--(15,15)); draw((15,15)--(0,15)); draw((0,15)--(0,0)); draw((0,5)--(15,10)); draw((15,5)--(0,10)); fill((7.5,2.5)--(7.5,12.5)--(5,7.5)--(10,7.5)--cycle,gray); label("A",(0,5),W); label("B",(15,10),E); [/asy]
50
What expression is never a prime number when $p$ is a prime number?
$p^2+26$
Given sets $A=\{x|x^{2}+2x-3=0,x\in R\}$ and $B=\{x|x^{2}-\left(a+1\right)x+a=0,x\in R\}$.<br/>$(1)$ When $a=2$, find $A\cap C_{R}B$;<br/>$(2)$ If $A\cup B=A$, find the set of real numbers for $a$.
\{1\}
A man has $2.73 in pennies, nickels, dimes, quarters and half dollars. If he has an equal number of coins of each kind, then the total number of coins he has is
15
Sue works in a factory and every 30 minutes, a machine she oversees produces 30 cans of soda. How many cans of soda can one machine produce in 8 hours?
Since there are 2 sets of 30 minutes in an hour, then in 8 hours there are 8 x 2 = <<8*2=16>>16 sets of 30 minutes. Hence, a machine that Sue oversees can produce 30 cans x 16 = <<30*16=480>>480 cans of soda in 8 hours. #### 480
A point $(x, y)$ is randomly selected such that $0 \leq x \leq 4$ and $0 \leq y \leq 5$. What is the probability that $x + y \leq 5$? Express your answer as a common fraction.
\frac{3}{5}
A collection of five positive integers has mean 4.4, unique mode 3 and median 4. If an 8 is added to the collection, what is the new median? Express your answer as a decimal to the nearest tenth.
4.5
Anthony keeps a bottle of vinegar in his cupboard for 2 years. Each year 20% of the vinegar evaporates. What percent of the vinegar is left after 2 years?
First find what percent of the vinegar is still in the bottle after each year: 100% - 20% = 80% Then multiply the amount of vinegar left after one year by the percentage left after each year to find how much is left after 2 years: 80% * 80% = 64% #### 64
Given a geometric sequence $\left\{a_{n}\right\}$ with real terms, and the sum of the first $n$ terms is $S_{n}$. If $S_{10} = 10$ and $S_{30} = 70$, calculate the value of $S_{40}$.
150
Square each integer $n$ in the range $1\le n\le 10$ and find the remainders when the squares are divided by $11$. Add up all the distinct results and call it $m$. What is the quotient when $m$ is divided by $11$?
2
Hanna has $300. She wants to buy roses at $2 each and give some of the roses to her friends, Jenna and Imma. Jenna will receive 1/3 of the roses, and Imma will receive 1/2 of the roses. How many roses does Hanna give to her friends?
Hanna can buy $300/$2 = <<300/2=150>>150 roses. So, Jenna will receive 1/3 x 150 = <<1/3*150=50>>50 roses. While Imma will receive 1/2 x 150 = <<1/2*150=75>>75 roses. Therefore, Hanna gives a total of 50 + 75 = <<50+75=125>>125 roses to her friends. #### 125
Consider the function $g(x) = \frac{x^2}{2} + 2x - 1$. Determine the sum of all distinct numbers $x$ such that $g(g(g(x))) = 1$.
-4
A bag of dozen apples costs $14 and Brian has already spent $10 on kiwis and half that much on bananas. What's the maximum number of apples Brian can buy if he left his house with only $50 and needs to pay the $3.50 subway fare each way?
Brian requires a total of $3.50 + $3.50 = $<<3.5+3.5=7>>7 to pay for the round trip subway fare We also know he has spent half (1/2) the amount he spent on kiwis on bananas, so he'll spend (1/2) * $10 = $5 on bananas So far in total he has spent $7 for his subway fare + $5 on bananas + $10 on kiwis = $7 + $5 + $10 = $<<7+5+10=22>>22 If he left his house with only $50, then all he will have left for apples would be $50 - $22 = $<<50-22=28>>28 If a bag of apples costs $14, then Brian would only be able to buy a maximum of $28/$14 = 2 bags of apples If each bag of apples has a dozen (12) apples, then (2) two bags will have 12*2= <<2*12=24>>24 apples #### 24
Compute $\cos 0^\circ$.
1
Sophie went to the Dunkin Donuts store and bought 4 boxes of donuts. There were 12 donuts in each box. She gave 1 box to her mom and half a dozen to her sister. How many donuts were left for her?
Sophie has 4 - 1 = <<4-1=3>>3 boxes of donuts left. The total number of pieces of donuts that she has is 3 x 12 = <<3*12=36>>36. She gave 12 / 2 = <<12/2=6>>6 donuts to her sister. Therefore Sophie was left with 36 - 6 = <<36-6=30>>30 donuts after giving her sister. #### 30
Given that a group of students is sitting evenly spaced around a circular table and a bag containing 120 pieces of candy is circulated among them, determine the possible number of students if Sam picks both the first and a final piece after the bag has completed exactly two full rounds.
60
Dan's skateboarding helmet has ten more craters than Daniel's ski helmet. Rin's snorkel helmet has 15 more craters than Dan's and Daniel's helmets combined. If Rin's helmet has 75 craters, how many craters are in Dan's helmet?
If Rin's snorkel helmet has 75 craters, then Dan's and Daniel's helmets combined have 75-15 = <<75-15=60>>60 craters. Let's assume Dan's helmet has C craters. Since Dan's skateboarding helmet has ten more craters than Daniel's ski helmet, the total number of craters their helmets have is C+(C-10)=60 2C=60+10 The total number of craters that Dan's helmet has is C=70/2 Dan's skateboarding helmet has 35 craters. #### 35
Given that in $\triangle ABC$, $C = 2A$, $\cos A = \frac{3}{4}$, and $2 \overrightarrow{BA} \cdot \overrightarrow{CB} = -27$. (I) Find the value of $\cos B$; (II) Find the perimeter of $\triangle ABC$.
15
The foot of the perpendicular from the origin to a plane is $(12,-4,3).$ Find the equation of the plane. Enter your answer in the form \[Ax + By + Cz + D = 0,\]where $A,$ $B,$ $C,$ $D$ are integers such that $A > 0$ and $\gcd(|A|,|B|,|C|,|D|) = 1.$
12x - 4y + 3z - 169 = 0
Collin has 25 flowers. Ingrid gives Collin a third of her 33 flowers. If each flower has 4 petals, how many petals does Collin have in total?
Ingrid gives Collin 33 / 3 = <<33/3=11>>11 flowers Now Collin has 25 + 11 = <<25+11=36>>36 flowers Since each flower has 4 petals, Collin has a total of 36 * 4 = <<36*4=144>>144 flowers #### 144
I have two 12-sided dice, each with 3 maroon sides, 4 teal sides, 4 cyan sides, and one sparkly side. If I roll both dice simultaneously, what is the probability that they will display the same color?
\frac{7}{24}
Suppose \( g(x) \) is a rational function such that \( 4g\left(\dfrac{1}{x}\right) + \dfrac{3g(x)}{x} = 2x^2 \) for \( x \neq 0 \). Find \( g(-3) \).
\frac{98}{13}
What is the value of $$ (x+1)(x+2006)\left[\frac{1}{(x+1)(x+2)}+\frac{1}{(x+2)(x+3)}+\ldots+\frac{1}{(x+2005)(x+2006)}\right] ? $$
2005
The fractional part of a positive number, its integer part, and the number itself form an increasing geometric progression. Find all such numbers.
\frac{\sqrt{5} + 1}{2}
A collection $\mathcal{S}$ of 10000 points is formed by picking each point uniformly at random inside a circle of radius 1. Let $N$ be the expected number of points of $\mathcal{S}$ which are vertices of the convex hull of the $\mathcal{S}$. (The convex hull is the smallest convex polygon containing every point of $\mathcal{S}$.) Estimate $N$.
72.8
Compute $\dbinom{8}{0}$.
1
Solve \[\arccos 2x - \arccos x = \frac{\pi}{3}.\]Enter all the solutions, separated by commas.
-\frac{1}{2}
Gabby is saving money to buy a new makeup set. The makeup set costs $65 and she already has $35. Gabby’s mom gives her an additional $20. How much money does Gabby need to buy the set?
Deduct the amount saved from the total cost of the set. $65 - $35 = $<<65-35=30>>30 Deduct the amount of money Gabby received from her mom. $30 - $20 = $<<30-20=10>>10 #### 10
Given the ellipse $$\frac {x^{2}}{a^{2}}+ \frac {y^{2}}{b^{2}}=1(a>b>0)$$ with eccentricity $$e= \frac { \sqrt {3}}{2}$$, A and B are the left and right vertices of the ellipse, respectively, and P is a point on the ellipse different from A and B. The angles of inclination of lines PA and PB are $\alpha$ and $\beta$, respectively. Then, $$\frac {cos(\alpha-\beta)}{cos(\alpha +\beta )}$$ equals \_\_\_\_\_\_.
\frac {3}{5}
How many of the integers between 1 and 1000, inclusive, can be expressed as the difference of the squares of two nonnegative integers?
750
A shop sells laptops at $600 each and a smartphone at $400. Celine buys two laptops and four smartphones for her children. How much change does she get back if she has $3000?
The cost of the two laptops is 2 x $600 = $<<2*600=1200>>1200. The cost of the four smartphones is 4 x $400 = $<<4*400=1600>>1600. Thus, the total cost of all the items is $1200 + $1600 = $<<1200+1600=2800>>2800. Therefore, Celine gets a change of $3000 - $2800 = $<<3000-2800=200>>200. #### 200
Each of five, standard, six-sided dice is rolled once. What is the probability that there is at least one pair but not a three-of-a-kind (that is, there are two dice showing the same value, but no three dice show the same value)?
\frac{25}{36}
Given that triangle XYZ is a right triangle with two altitudes of lengths 6 and 18, determine the largest possible integer length for the third altitude.
12
Sarah's bowling score was 40 points more than Greg's, and the average of their two scores was 102. What was Sarah's score? (Recall that the average of two numbers is their sum divided by 2.)
122
Masha talked a lot on the phone with her friends, and the charged battery discharged exactly after a day. It is known that the charge lasts for 5 hours of talk time or 150 hours of standby time. How long did Masha talk with her friends?
126/29
Given that the function $y=f(x)$ is an odd function defined on $\mathbb{R}$ and $f(-1)=2$, and the period of the function is $4$, calculate the values of $f(2012)$ and $f(2013)$.
-2
Kamil wants to renovate his kitchen at home. For this purpose, he hired two professionals who work for him 6 hours a day for 7 days. What does it cost Kamil to hire these professionals if one of them is paid $15 per hour of work?
Two professionals work together 6 * 2 = <<6*2=12>>12 hours per day. They work for 7 days, so in total it means 7 * 12 = <<7*12=84>>84 hours. The cost of hiring these persons is 84 * 15 = $<<84*15=1260>>1260. #### 1260
Determine the smallest natural number $n$ for which there exist distinct nonzero naturals $a, b, c$ , such that $n=a+b+c$ and $(a + b)(b + c)(c + a)$ is a perfect cube.
10
There are six students with unique integer scores in a mathematics exam. The average score is 92.5, the highest score is 99, and the lowest score is 76. What is the minimum score of the student who ranks 3rd from the highest?
95
Abby, Bernardo, Carl, and Debra play a game in which each of them starts with four coins. The game consists of four rounds. In each round, four balls are placed in an urn---one green, one red, and two white. The players each draw a ball at random without replacement. Whoever gets the green ball gives one coin to whoever gets the red ball. What is the probability that, at the end of the fourth round, each of the players has four coins?
\frac{5}{192}
Given that $a > 0$ and $b > 0$, if the inequality $\frac{3}{a} + \frac{1}{b} \geq \frac{m}{a + 3b}$ always holds true, find the maximum value of $m$.
12
Let $x$ and $y$ be real numbers such that $3x + 2y \le 7$ and $2x + 4y \le 8.$ Find the largest possible value of $x + y.$
\frac{11}{4}
A given sequence $r_1, r_2, \dots, r_n$ of distinct real numbers can be put in ascending order by means of one or more "bubble passes". A bubble pass through a given sequence consists of comparing the second term with the first term, and exchanging them if and only if the second term is smaller, then comparing the third term with the second term and exchanging them if and only if the third term is smaller, and so on in order, through comparing the last term, $r_n$, with its current predecessor and exchanging them if and only if the last term is smaller. The example below shows how the sequence 1, 9, 8, 7 is transformed into the sequence 1, 8, 7, 9 by one bubble pass. The numbers compared at each step are underlined. $\underline{1 \quad 9} \quad 8 \quad 7$ $1 \quad {}\underline{9 \quad 8} \quad 7$ $1 \quad 8 \quad \underline{9 \quad 7}$ $1 \quad 8 \quad 7 \quad 9$ Suppose that $n = 40$, and that the terms of the initial sequence $r_1, r_2, \dots, r_{40}$ are distinct from one another and are in random order. Let $p/q$, in lowest terms, be the probability that the number that begins as $r_{20}$ will end up, after one bubble pass, in the $30^{\mbox{th}}$ place. Find $p + q$.
931
There are 4 different digits that can form 18 different four-digit numbers arranged in ascending order. The first four-digit number is a perfect square, and the second-last four-digit number is also a perfect square. What is the sum of these two numbers?
10890
4 friends are running a 4 x 100 relay race. Mary ran first and took twice as long as Susan. Susan ran second and she took 10 seconds longer than Jen. Jen ran third and finished in 30 seconds. Tiffany ran the last leg and finished in 7 seconds less than Mary. How many seconds did it take the team to finish the race?
Susan's time was 30 seconds + 10 seconds = <<30+10=40>>40 seconds. Mary's time was 40 seconds * 2 = <<40*2=80>>80 seconds. Tiffany's time was 80 seconds - 7 seconds = <<80-7=73>>73 seconds. The total time for the team was 80 seconds + 40 seconds + 30 seconds + 73 seconds = <<80+40+30+73=223>>223 seconds. #### 223
A school has between 150 and 200 students enrolled. Every afternoon, all the students come together to participate in gym class. The students are separated into six distinct sections of students. If one student is absent from school, the sections can all have the same number of students. What is the sum of all possible numbers of students enrolled at the school?
1575