Difference between revisions of "2024 AIME II Problems"
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Let <math>x,y</math> and <math>z</math> be positive real numbers that satisfy the following system of equations: | Let <math>x,y</math> and <math>z</math> be positive real numbers that satisfy the following system of equations: | ||
<cmath>\log_2\left({x \over yz}\right) = {1 \over 2}</cmath><cmath>\log_2\left({y \over xz}\right) = {1 \over 3}</cmath><cmath>\log_2\left({z \over xy}\right) = {1 \over 4}</cmath> | <cmath>\log_2\left({x \over yz}\right) = {1 \over 2}</cmath><cmath>\log_2\left({y \over xz}\right) = {1 \over 3}</cmath><cmath>\log_2\left({z \over xy}\right) = {1 \over 4}</cmath> | ||
− | Then the value of <math>\left|\log_2(x^4y^3z^2)\right|</math> is <math>{m | + | Then the value of <math>\left|\log_2(x^4y^3z^2)\right|</math> is <math>\tfrac{m}{n}</math> where <math>m</math> and <math>n</math> are relatively prime positive integers. Find <math>m+n</math>. |
Line 43: | Line 43: | ||
==Problem 5== | ==Problem 5== | ||
− | + | Let <math>ABCDEF</math> be a convex equilateral hexagon in which all pairs of opposite sides are parallel. The triangle whose sides are extensions of segments <math>\overline{AB}</math>, <math>\overline{CD}</math>, and <math>\overline{EF}</math> has side lengths <math>200, 240,</math> and <math>300</math>. Find the side length of the hexagon. | |
[[2024 AIME II Problems/Problem 5|Solution]] | [[2024 AIME II Problems/Problem 5|Solution]] | ||
==Problem 6== | ==Problem 6== | ||
− | + | Alice chooses a set <math>A</math> of positive integers. Then Bob lists all finite nonempty sets <math>B</math> of positive integers with the property that the maximum element of <math>B</math> belongs to <math>A</math>. Bob's list has <math>2024</math> sets. Find the sum of the elements of <math>A</math>. | |
− | |||
[[2024 AIME II Problems/Problem 6|Solution]] | [[2024 AIME II Problems/Problem 6|Solution]] | ||
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==Problem 8== | ==Problem 8== | ||
+ | Torus <math>T</math> is the surface produced by revolving a circle with radius 3 around an axis in the plane of the circle that is a distance 6 from the center of the circle (so like a donut). Let <math>S</math> be a sphere with a radius 11. When <math>T</math> rests on the inside of <math>S</math>, it is internally tangent to <math>S</math> along a circle with radius <math>r_i</math>, and when <math>T</math> rests on the outside of <math>S</math>, it is externally tangent to <math>S</math> along a circle with radius <math>r_o</math>. The difference <math>r_i-r_o</math> can be written as <math>\frac{m}{n}</math>, where <math>m</math> and <math>n</math> are relatively prime positive integers. Find <math>m+n</math>. | ||
+ | <asy> | ||
+ | unitsize(0.3 inch); | ||
+ | draw(ellipse((0,0), 3, 1.75)); | ||
+ | draw((-1.2,0.1)..(-0.8,-0.03)..(-0.4,-0.11)..(0,-0.15)..(0.4,-0.11)..(0.8,-0.03)..(1.2,0.1)); | ||
+ | draw((-1,0.04)..(-0.5,0.12)..(0,0.16)..(0.5,0.12)..(1,0.04)); | ||
+ | draw((0,2.4)--(0,-0.15)); | ||
+ | draw((0,-0.15)--(0,-1.75), dashed); | ||
+ | draw((0,-1.75)--(0,-2.25)); | ||
+ | draw(ellipse((2,0), 1, 0.9)); | ||
+ | draw((2.03,-0.02)--(2.9,-0.4)); | ||
+ | </asy> | ||
[[2024 AIME II Problems/Problem 8|Solution]] | [[2024 AIME II Problems/Problem 8|Solution]] | ||
==Problem 9== | ==Problem 9== | ||
+ | There are <math>25</math> indistinguishable white chips and <math>25</math> indistinguishable black chips. Find the number of ways to place some of these chips in a <math>5 \times 5</math> grid such that | ||
+ | |||
+ | * each cell contains at most one chip | ||
+ | |||
+ | * all chips in the same row and all chips in the same column have the same colour | ||
+ | * any additional chip placed on the grid would violate one or more of the previous two conditions. | ||
[[2024 AIME II Problems/Problem 9|Solution]] | [[2024 AIME II Problems/Problem 9|Solution]] | ||
==Problem 10== | ==Problem 10== | ||
− | + | Let <math>\triangle</math><math>ABC</math> have incenter <math>I</math> and circumcenter <math>O</math> with <math>\overline{IA} \perp \overline{OI}</math>, circumradius <math>13</math>, and inradius <math>6</math>. Find <math>AB \cdot AC</math>. | |
− | |||
[[2024 AIME II Problems/Problem 10|Solution]] | [[2024 AIME II Problems/Problem 10|Solution]] | ||
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==Problem 12== | ==Problem 12== | ||
− | + | Let <math>O(0,0),A(\tfrac{1}{2},0),</math> and <math>B(0,\tfrac{\sqrt{3}}{2})</math> be points in the coordinate plane. Let <math>\mathcal{F}</math> be the family of segments <math>\overline{PQ}</math> of unit length lying in the first quadrant with <math>P</math> on the <math>x</math>-axis and <math>Q</math> on the <math>y</math>-axis. There is a unique point <math>C</math> on <math>\overline{AB},</math> distinct from <math>A</math> and <math>B,</math> that does not belong to any segment from <math>\mathcal{F}</math> other than <math>\overline{AB}</math>. Then <math>OC^2=\tfrac{p}{q}</math>, where <math>p</math> and <math>q</math> are relatively prime positive integers. Find <math>p+q</math>. | |
− | |||
[[2024 AIME II Problems/Problem 12|Solution]] | [[2024 AIME II Problems/Problem 12|Solution]] | ||
Line 98: | Line 113: | ||
==Problem 14== | ==Problem 14== | ||
− | Let <math>b \geq 2</math> be an integer. Call a positive integer <math>n</math> <math>b</math> | + | Let <math>b \geq 2</math> be an integer. Call a positive integer <math>n</math> <math>b\textit{-eautiful}</math> if it has exactly two digits when expressed in base <math>b</math>, and these two digits sum to <math>\sqrt{n}</math>. For example, <math>81</math> is <math>13</math>-eautiful because <math>81=\underline{6}</math><math>\underline{3}_{13}</math> and <math>6+3=\sqrt{81}</math>. Find the least integer <math>b\geq 2</math> for which there are more than ten <math>b</math>-eautiful integers. |
[[2024 AIME II Problems/Problem 14|Solution]] | [[2024 AIME II Problems/Problem 14|Solution]] | ||
==Problem 15== | ==Problem 15== | ||
+ | Find the number of rectangles that can be formed inside a fixed regular dodecagon (<math>12</math>-gon) where each side of the rectangle lies on either a side or a diagonal of the dodecagon. The diagram below shows three of those rectangles. | ||
− | + | <asy> | |
+ | unitsize(0.6 inch); | ||
+ | for(int i=0; i<360; i+=30) { | ||
+ | dot(dir(i), 4+black); | ||
+ | draw(dir(i)--dir(i+30)); | ||
+ | } | ||
+ | draw(dir(120)--dir(330)); | ||
+ | filldraw(dir(210)--dir(240)--dir(30)--dir(60)--cycle, mediumgray, linewidth(1.5)); | ||
+ | draw((0,0.366)--(0.366,0), linewidth(1.5)); | ||
+ | </asy> | ||
[[2024 AIME II Problems/Problem 15|Solution]] | [[2024 AIME II Problems/Problem 15|Solution]] |
Latest revision as of 08:59, 29 July 2024
2024 AIME II (Answer Key) | AoPS Contest Collections • PDF | ||
Instructions
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1 • 2 • 3 • 4 • 5 • 6 • 7 • 8 • 9 • 10 • 11 • 12 • 13 • 14 • 15 |
Contents
Problem 1
Among the residents of Aimeville, there are who own a diamond ring, who own a set of golf clubs, and who own a garden spade. In addition, each of the residents owns a bag of candy hearts. There are residents who own exactly two of these things, and residents who own exactly three of these things. Find the number of residents of Aimeville who own all four of these things.
Problem 2
A list of positive integers has the following properties:
The sum of the items in the list is .
The unique mode of the list is .
The median of the list is a positive integer that does not appear in the list itself.
Find the sum of the squares of all the items in the list.
Problem 3
Find the number of ways to place a digit in each cell of a 2x3 grid so that the sum of the two numbers formed by reading left to right is , and the sum of the three numbers formed by reading top to bottom is . The grid below is an example of such an arrangement because and .
Problem 4
Let and be positive real numbers that satisfy the following system of equations: Then the value of is where and are relatively prime positive integers. Find .
Problem 5
Let be a convex equilateral hexagon in which all pairs of opposite sides are parallel. The triangle whose sides are extensions of segments , , and has side lengths and . Find the side length of the hexagon.
Problem 6
Alice chooses a set of positive integers. Then Bob lists all finite nonempty sets of positive integers with the property that the maximum element of belongs to . Bob's list has sets. Find the sum of the elements of .
Problem 7
Let be the greatest four-digit integer with the property that whenever one of its digits is changed to , the resulting number is divisible by . Let and be the quotient and remainder, respectively, when is divided by . Find .
Problem 8
Torus is the surface produced by revolving a circle with radius 3 around an axis in the plane of the circle that is a distance 6 from the center of the circle (so like a donut). Let be a sphere with a radius 11. When rests on the inside of , it is internally tangent to along a circle with radius , and when rests on the outside of , it is externally tangent to along a circle with radius . The difference can be written as , where and are relatively prime positive integers. Find .
Problem 9
There are indistinguishable white chips and indistinguishable black chips. Find the number of ways to place some of these chips in a grid such that
- each cell contains at most one chip
- all chips in the same row and all chips in the same column have the same colour
- any additional chip placed on the grid would violate one or more of the previous two conditions.
Problem 10
Let have incenter and circumcenter with , circumradius , and inradius . Find .
Problem 11
Find the number of triples of nonnegative integers satisfying and
Problem 12
Let and be points in the coordinate plane. Let be the family of segments of unit length lying in the first quadrant with on the -axis and on the -axis. There is a unique point on distinct from and that does not belong to any segment from other than . Then , where and are relatively prime positive integers. Find .
Problem 13
Let be a 13th root of unity. Find the remainder when is divided by 1000.
Problem 14
Let be an integer. Call a positive integer if it has exactly two digits when expressed in base , and these two digits sum to . For example, is -eautiful because and . Find the least integer for which there are more than ten -eautiful integers.
Problem 15
Find the number of rectangles that can be formed inside a fixed regular dodecagon (-gon) where each side of the rectangle lies on either a side or a diagonal of the dodecagon. The diagram below shows three of those rectangles.
See also
2024 AIME II (Problems • Answer Key • Resources) | ||
Preceded by 2024 AIME I |
Followed by 2025 AIME I | |
1 • 2 • 3 • 4 • 5 • 6 • 7 • 8 • 9 • 10 • 11 • 12 • 13 • 14 • 15 | ||
All AIME Problems and Solutions |
- American Invitational Mathematics Examination
- AIME Problems and Solutions
- Mathematics competition resources
The problems on this page are copyrighted by the Mathematical Association of America's American Mathematics Competitions.