Difference between revisions of "2024 AMC 8 Problems"

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{{AMC8 Problems|year=2024|}}
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SKIBIDI Toilet Vs. Grimace Shake
==Problem 1==
 
What is the ones digit of <cmath>222,222-22,222-2,222-222-22-2?</cmath>
 
<math>\textbf{(A) } 0\qquad\textbf{(B) } 2\qquad\textbf{(C) } 4\qquad\textbf{(D) } 6\qquad\textbf{(E) } 8</math>
 
 
 
[[2024 AMC 8 Problems/Problem 1|Solution]]
 
 
 
==Problem 2==
 
What is the value of this expression in decimal form?
 
<cmath>\frac{44}{11} + \frac{110}{44} + \frac{44}{1100}</cmath>
 
 
 
<math>\textbf{(A) } 6.4\qquad\textbf{(B) } 6.504\qquad\textbf{(C) } 6.54\qquad\textbf{(D) } 6.9\qquad\textbf{(E) } 6.94</math>
 
 
 
[[2024 AMC 8 Problems/Problem 2|Solution]]
 
 
 
==Problem 3==
 
 
 
Four squares of side lengths <math>4</math>, <math>7</math>, <math>9</math>, and <math>10</math> units are arranged in increasing size order so that their left edges and bottom edges align. The squares alternate in the color pattern white-gray-white-gray, respectively, as shown in the figure. What is the area of the visible gray region in square units?
 
 
 
<asy>
 
size(150);
 
filldraw((0,0)--(10,0)--(10,10)--(0,10)--cycle,gray(0.7),linewidth(1));
 
filldraw((0,0)--(9,0)--(9,9)--(0,9)--cycle,white,linewidth(1));
 
filldraw((0,0)--(7,0)--(7,7)--(0,7)--cycle,gray(0.7),linewidth(1));
 
filldraw((0,0)--(4,0)--(4,4)--(0,4)--cycle,white,linewidth(1));
 
draw((11,0)--(11,4),linewidth(1));
 
draw((11,6)--(11,10),linewidth(1));
 
label("$10$",(11,5),fontsize(14pt));
 
draw((10.75,0)--(11.25,0),linewidth(1));
 
draw((10.75,10)--(11.25,10),linewidth(1));
 
draw((0,11)--(4,11),linewidth(1));
 
draw((6,11)--(9,11),linewidth(1));
 
draw((0,11.25)--(0,10.75),linewidth(1));
 
draw((9,11.25)--(9,10.75),linewidth(1));
 
label("$9$",(5,11),fontsize(14pt));
 
draw((-1,0)--(-1,1),linewidth(1));
 
draw((-1,3)--(-1,7),linewidth(1));
 
draw((-1.25,0)--(-0.75,0),linewidth(1));
 
draw((-1.25,7)--(-0.75,7),linewidth(1));
 
label("$7$",(-1,2),fontsize(14pt));
 
draw((0,-1)--(1,-1),linewidth(1));
 
draw((3,-1)--(4,-1),linewidth(1));
 
draw((0,-1.25)--(0,-.75),linewidth(1));
 
draw((4,-1.25)--(4,-.75),linewidth(1));
 
label("$4$",(2,-1),fontsize(14pt));
 
</asy>
 
 
 
<math>\textbf{(A)}\ 42 \qquad \textbf{(B)}\ 45 \qquad \textbf{(C)}\ 49 \qquad \textbf{(D)}\ 50 \qquad \textbf{(E)}\ 52</math>
 
 
 
[[2024 AMC 8 Problems/Problem 3|Solution]]
 
 
 
==Problem 4==
 
When Yunji added all the integers from <math>1</math> to <math>9</math>, she mistakenly left out a number. Her incorrect sum turned out to be a square number. What number did Yunji leave out?
 
 
 
<math>\textbf{(A) } 5\qquad\textbf{(B) } 6\qquad\textbf{(C) } 7\qquad\textbf{(D) } 8\qquad\textbf{(E) } 9</math>
 
 
 
[[2024 AMC 8 Problems/Problem 4|Solution]]
 
 
 
==Problem 5==
 
Aaliyah rolls two standard 6-sided dice. She notices that the product of the two numbers rolled is a multiple of <math>6</math>. Which of the following integers cannot be the sum of the two numbers?
 
 
 
<math>\textbf{(A) } 5\qquad\textbf{(B) } 6\qquad\textbf{(C) } 7\qquad\textbf{(D) } 8\qquad\textbf{(E) } 9</math>
 
 
 
[[2024 AMC 8 Problems/Problem 5|Solution]]
 
 
 
==Problem 6==
 
 
 
Sergei skated around an ice rink, gliding along different paths. The gray lines in the figures below show four of the paths labeled <math>P</math>, <math>Q</math>, <math>R</math>, and <math>S.</math> What is the sorted order of the four paths from shortest to longest?
 
 
 
[Diagram Required]
 
 
 
<math>\textbf{(A)}\ P,Q,R,S \qquad \textbf{(B)}\ P,R,S,Q \qquad \textbf{(C)}\ Q,S,P,R \qquad \textbf{(D)}\ R,P,S,Q \qquad \textbf{(E)}\ R,S,P,Q</math>
 
 
 
[[2024 AMC 8 Problems/Problem 6|Solution]]
 
 
 
==Problem 7==
 
A <math>3</math>x<math>7</math> rectangle is covered without overlap by 3 shapes of tiles: <math>2</math>x<math>2</math>, <math>1</math>x<math>4</math>, and <math>1</math>x<math>1</math>, shown below. What is the minimum possible number of <math>1</math>x<math>1</math> tiles used?
 
 
 
[[File:2024-AMC8-q7.png]]
 
 
 
<math>\textbf{(A) } 1\qquad\textbf{(B)} 2\qquad\textbf{(C) } 3\qquad\textbf{(D) } 4\qquad\textbf{(E) } 5</math>
 
 
 
[[2024 AMC 8 Problems/Problem 7|Solution]]
 
 
 
==Problem 8==
 
On Monday Taye has \$2. Every day, he either gains \$3 or doubles the amount of money he had on the previous day. How many different dollar amounts could Taye have on Thursday, 3 days later?
 
 
 
<math>\textbf{(A) } 3\qquad\textbf{(B) } 4\qquad\textbf{(C) } 5\qquad\textbf{(D) } 6\qquad\textbf{(E) } 7</math>
 
 
 
[[2024 AMC 8 Problems/Problem 8|Solution]]
 
 
 
==Problem 9==
 
All the marbles in Maria's collection are red, green, or blue. Maria has half as many red marbles as green marbles and twice as many blue marbles as green marbles. Which of the following could be the total number of marbles in Maria's collection?
 
 
 
<math>\textbf{(A) } 24\qquad\textbf{(B) } 25\qquad\textbf{(C) } 26\qquad\textbf{(D) } 27\qquad\textbf{(E) } 28</math>
 
 
 
[[2024 AMC 8 Problems/Problem 9|Solution]]
 
 
 
==Problem 10==
 
 
 
In January 1980 the Moana Loa Observation recorded carbon dioxide <math>(CO_2)</math> levels of 338 ppm (parts per million). Over the years the average <math>CO_2</math> reading has increased by about 1.515 ppm each year. What is the expected <math>CO_2</math> level in ppm in January 2030? Round your answer to the nearest integer.
 
 
 
<math>\textbf{(A)}\ 399 \qquad \textbf{(B)}\ 414 \qquad \textbf{(C)}\ 420 \qquad \textbf{(D)}\ 444 \qquad \textbf{(E)}\ 459</math>
 
 
 
[[2024 AMC 8 Problems/Problem 10|Solution]]
 
 
 
==Problem 12==
 
 
 
Rohan keeps a total of 90 guppies in 4 fish tanks.
 
There is 1 more guppy in the 2nd tank than the 1st tank.
 
There are 2 more guppies in the 3rd tank than the 2nd tank.
 
There are 3 more guppies in the 4th tank than the 3rd tank.
 
How many guppies are in the 4th tank?
 
 
 
<math>\textbf{(A)}\ 20 \qquad \textbf{(B)}\ 21 \qquad \textbf{(C)}\ 23 \qquad \textbf{(D)}\ 24 \qquad \textbf{(E)}\ 26</math>
 
 
 
[[2024 AMC 8 Problems/Problem 12|Solution]]
 
 
 
==Problem 13==
 
Buzz Bunny is hopping up and down a set of stairs, one step at a time. In how many ways can Buzz start on the ground, make a sequence of <math>6</math> hops, and end up back on the ground?
 
(For example, one sequence of hops is up-up-down-down-up-down.)
 
 
 
[[File:2024-AMC8-q13.png]]
 
 
 
 
 
<math>\textbf{(A)}\ 4 \qquad \textbf{(B)}\ 5 \qquad \textbf{(C)}\ 6 \qquad \textbf{(D)}\ 8 \qquad \textbf{(E)}\ 12</math>
 
 
 
[[2024 AMC 8 Problems/Problem 13|Solution]]
 
 
 
==Problem 14==
 
The one-way routes connecting towns <math>A,M,C,X,Y,</math> and <math>Z</math> are shown in the figure below (not drawn to scale).The distances in kilometers along each route are marked. Traveling along these routes, what is the shortest distance from A to Z in kilometers?
 
 
 
[[File:2024-AMC8-q14.png]]
 
 
 
<math>\textbf{(A)}\ 28 \qquad \textbf{(B)}\ 29 \qquad \textbf{(C)}\ 30 \qquad \textbf{(D)}\ 31 \qquad \textbf{(E)}\ 32</math>
 
 
 
[[2024 AMC 8 Problems/Problem 14|Solution]]
 
 
 
==Problem 15==
 
 
 
Let the letters <math>F</math>,<math>L</math>,<math>Y</math>,<math>B</math>,<math>U</math>,<math>G</math> represent distinct digits. Suppose <math>\underline{F}~\underline{L}~\underline{Y}~\underline{F}~\underline{L}~\underline{Y}</math> is the greatest number that satisfies the equation
 
 
 
<cmath>8\cdot\underline{F}~\underline{L}~\underline{Y}~\underline{F}~\underline{L}~\underline{Y}=\underline{B}~\underline{U}~\underline{G}~\underline{B}~\underline{U}~\underline{G}.</cmath>
 
 
 
What is the value of <math>\underline{F}~\underline{L}~\underline{Y}+\underline{B}~\underline{U}~\underline{G}</math>?
 
 
 
<math>\textbf{(A)}\ 1089 \qquad \textbf{(B)}\ 1098 \qquad \textbf{(C)}\ 1107 \qquad \textbf{(D)}\ 1116 \qquad \textbf{(E)}\ 1125</math>
 
 
 
[[2024 AMC 8 Problems/Problem 15|Solution]]
 
 
 
==Problem 16==
 
Minh enters the numbers <math>1</math> through <math>81</math> into the cells of a <math>9 \times 9</math> grid in some order. She calculates the product of the numbers in each row and column. What is the least number of rows and columns that could have a product divisible by <math>3</math>?
 
 
 
<math>\textbf{(A) } 8\qquad\textbf{(B) } 9\qquad\textbf{(C) } 10\qquad\textbf{(D) } 11\qquad\textbf{(E) } 12</math>
 
 
 
[[2024 AMC 8 Problems/Problem 16|Solution]]
 
 
 
==Problem 17==
 
A chess king is said to attack all squares one step away from it, horizontally, vertically, or diagonally. For instance, a king on the center square of a 3 x 3 grid attacks all 8 other squares, as shown below. Suppose a white king and a black king are placed on different squares of 3 x 3 grid so that they do not attack each other. In how many ways can this be done?
 
 
 
<asy>
 
/* AMC8 P17 2024, revised by Teacher David */
 
unitsize(29pt);
 
import math;
 
add(grid(3,3));
 
 
 
pair [] a = {(0.5,0.5), (0.5, 1.5), (0.5, 2.5), (1.5, 2.5), (2.5,2.5), (2.5,1.5), (2.5,0.5), (1.5,0.5)};
 
 
 
for (int i=0; i<a.length; ++i) {
 
    pair x = (1.5,1.5) + 0.4*dir(225-45*i);
 
    draw(x -- a[i], arrow=EndArrow());
 
}
 
 
 
label("$K$", (1.5,1.5));
 
</asy>
 
 
 
<math>\textbf{(A)}\ 20 \qquad \textbf{(B)}\ 24 \qquad \textbf{(C)}\ 27 \qquad \textbf{(D)}\ 28 \qquad \textbf{(E)}\ 32</math>
 
 
 
[[2024 AMC 8 Problems/Problem 17|Solution]]
 
 
 
==Problem 18==
 
 
 
Three concentric circles centered at <math>O</math> have radii of <math>1</math>, <math>2</math>, and <math>3</math>. Points <math>B</math> and <math>C</math> lie on the largest circle. The region between the two smaller circles is shaded, as is the portion of the region between the two larger circles bounded by central angle <math>BOC</math>, as shown in the figure below. Suppose the shaded and unshaded regions are equal in area. What is the measure of <math>\angle{BOC}</math> in degrees?
 
 
 
<asy>
 
size(150);
 
import graph;
 
 
 
draw(circle((0,0),3));
 
real radius = 3;
 
real angleStart = -54;  // starting angle of the sector
 
real angleEnd = 54;  // ending angle of the sector
 
label("$O$",(0,0),W);
 
pair O = (0, 0);
 
filldraw(arc(O, radius, angleStart, angleEnd)--O--cycle, gray);
 
filldraw(circle((0,0),2),gray);
 
filldraw(circle((0,0),1),white);
 
draw((1.763,2.427)--(0,0)--(1.763,-2.427));
 
label("$B$",(1.763,2.427),NE);
 
label("$C$",(1.763,-2.427),SE);
 
</asy>
 
 
 
<math>\textbf{(A)}\ 108 \qquad \textbf{(B)}\ 120 \qquad \textbf{(C)}\ 135 \qquad \textbf{(D)}\ 144 \qquad \textbf{(E)}\ 150</math>
 
 
 
[[2024 AMC 8 Problems/Problem 18|Solution]]
 
 
 
==Problem 19==
 
Jordan owns 15 pairs of sneakers. Three fifths of the pairs are red and the rest are white. Two thirds of the pairs are high-top and the rest are low-top. The red high-top sneakers make up a fraction of the collection. What is the least possible value of this fraction?
 
 
 
<math>\textbf{(A) } 0\qquad\textbf{(B) } \dfrac{1}{5} \qquad\textbf{(C) } \dfrac{4}{15} \qquad\textbf{(D) } \dfrac{1}{3} \qquad\textbf{(E) } \dfrac{2}{5}</math>
 
 
 
[[2024 AMC 8 Problems/Problem 19|Solution]]
 
 
 
==Problem 20==
 
Any three vertices of the cube <math>PQRSTUVW,</math> shown in the figure below, can be connected to form a triangle. <math>(</math>For example, vertices <math>P, Q,</math> and <math>R</math> can be connected to form <math>\triangle{PQR}.)</math> How many of these triangles are equilateral and contain <math>P</math> as a vertex?
 
 
 
<asy>
 
unitsize(4);
 
pair P,Q,R,S,T,U,V,W;
 
P=(0,30); Q=(30,30); R=(40,40); S=(10,40); T=(10,10); U=(40,10); V=(30,0); W=(0,0);
 
draw(W--V); draw(V--Q); draw(Q--P); draw(P--W); draw(T--U); draw(U--R); draw(R--S); draw(S--T); draw(W--T); draw(P--S); draw(V--U); draw(Q--R);
 
dot(P);
 
dot(Q);
 
dot(R);
 
dot(S);
 
dot(T);
 
dot(U);
 
dot(V);
 
dot(W);
 
label("$P$",P,NW);
 
label("$Q$",Q,NW);
 
label("$R$",R,NE);
 
label("$S$",S,N);
 
label("$T$",T,NE);
 
label("$U$",U,NE);
 
label("$V$",V,SE);
 
label("$W$",W,SW);
 
</asy>
 
 
 
<math>\textbf{(A) }0\qquad\textbf{(B) }1\qquad\textbf{(C) }2\qquad\textbf{(D) }3\qquad\textbf{(E) }6</math>
 
 
 
[[2024 AMC 8 Problems/Problem 20|Solution]]
 
 
 
==Problem 21==
 
A group of frogs (called an army) is living in a tree. A frog turns green when in the shade and turns yellow
 
when in the sun. Initially, the ratio of green to yellow frogs was <math>3 : 1</math>. Then <math>3</math> green frogs moved to the
 
sunny side and <math>5</math> yellow frogs moved to the shady side. Now the ratio is <math>4 : 1</math>. What is the difference
 
between the number of green frogs and the number of yellow frogs now?
 
 
 
<math>\textbf{(A) } 10\qquad\textbf{(B) } 12\qquad\textbf{(C) } 16\qquad\textbf{(D) } 20\qquad\textbf{(E) } 24</math>
 
 
 
[[2024 AMC 8 Problems/Problem 21|Solution]]
 
 
 
==Problem 22==
 
A  roll of tape is 4 inches in diameter and is wrapped around a ring that is 2 inches in diameter. A cross section of the tape is shown in the figure below. The tape is 0.015 inches thick. If the tape is completely unrolled, approximately how long would it be? Round your answer to the nearest 100 inches.
 
 
 
<math>\textbf{(A) } 300\qquad\textbf{(B)} 600\qquad\textbf{(C) } 1200\qquad\textbf{(D) } 1500\qquad\textbf{(E) } 1800</math>
 
 
 
[[2024 AMC 8 Problems/Problem 22|Solution]]
 
 
 
==Problem 23==
 
 
 
Rodrigo has a very large sheet of graph paper. First he draws a line segment connecting point <math>(0,4)</math> to point <math>(2,0)</math> and colors the <math>4</math> cells whose interiors intersect the segment, as shown below. Next Rodrigo draws a line segment connecting point <math>(2000,3000)</math> to point <math>(5000,8000)</math>. How many cells will he color this time?
 
 
 
<asy>
 
 
 
filldraw((0,4)--(1,4)--(1,3)--(0,3)--cycle, gray(.75), gray(.5)+linewidth(1));
 
filldraw((0,3)--(1,3)--(1,2)--(0,2)--cycle, gray(.75), gray(.5)+linewidth(1));
 
filldraw((1,2)--(2,2)--(2,1)--(1,1)--cycle, gray(.75), gray(.5)+linewidth(1));
 
filldraw((1,1)--(2,1)--(2,0)--(1,0)--cycle, gray(.75), gray(.5)+linewidth(1));
 
 
 
draw((-1,5)--(-1,-1),gray(.9));
 
draw((0,5)--(0,-1),gray(.9));
 
draw((1,5)--(1,-1),gray(.9));
 
draw((2,5)--(2,-1),gray(.9));
 
draw((3,5)--(3,-1),gray(.9));
 
draw((4,5)--(4,-1),gray(.9));
 
draw((5,5)--(5,-1),gray(.9));
 
 
 
draw((-1,5)--(5, 5),gray(.9));
 
draw((-1,4)--(5,4),gray(.9));
 
draw((-1,3)--(5,3),gray(.9));
 
draw((-1,2)--(5,2),gray(.9));
 
draw((-1,1)--(5,1),gray(.9));
 
draw((-1,0)--(5,0),gray(.9));
 
draw((-1,-1)--(5,-1),gray(.9));
 
 
 
 
 
dot((0,4));
 
label("$(0,4)$",(0,4),NW);
 
 
 
dot((2,0));
 
label("$(2,0)$",(2,0),SE);
 
 
 
draw((0,4)--(2,0));
 
 
 
draw((-1,0) -- (5,0), arrow=Arrow);
 
draw((0,-1) -- (0,5), arrow=Arrow);
 
 
 
</asy>
 
 
 
<math>\textbf{(A) }6000\qquad\textbf{(B) }6500\qquad\textbf{(C) }7000\qquad\textbf{(D) }7500\qquad\textbf{(E) }8000</math>
 
 
 
[[2024 AMC 8 Problems/Problem 23|Solution]]
 
 
 
==Problem 24==
 
 
 
Jean has made a piece of stained glass art in the shape of two mountains, as shown in the figure below. One mountain peak is <math>8</math> feet high while the other peak is <math>12</math> feet high. Each peak forms a <math>90^\circ</math> angle, and the straight sides form a <math>45^\circ</math> angle with the ground. The artwork has an area of <math>183</math> square feet. The sides of the mountain meet at an intersection point near the center of the artwork, <math>h</math> feet above the ground. What is the value of <math>h?</math>
 
 
 
<asy>
 
unitsize(.3cm);
 
filldraw((0,0)--(8,8)--(11,5)--(18,12)--(30,0)--cycle,gray(0.7),linewidth(1));
 
draw((-1,0)--(-1,8),linewidth(.75));
 
draw((-1.4,0)--(-.6,0),linewidth(.75));
 
draw((-1.4,8)--(-.6,8),linewidth(.75));
 
label("$8$",(-1,4),W);
 
label("$12$",(31,6),E);
 
draw((-1,8)--(8,8),dashed);
 
draw((31,0)--(31,12),linewidth(.75));
 
draw((30.6,0)--(31.4,0),linewidth(.75));
 
draw((30.6,12)--(31.4,12),linewidth(.75));
 
draw((31,12)--(18,12),dashed);
 
label("$45^{\circ}$",(.75,0),NE,fontsize(10pt));
 
label("$45^{\circ}$",(29.25,0),NW,fontsize(10pt));
 
draw((8,8)--(7.5,7.5)--(8,7)--(8.5,7.5)--cycle);
 
draw((18,12)--(17.5,11.5)--(18,11)--(18.5,11.5)--cycle);
 
draw((11,5)--(11,0),dashed);
 
label("$h$",(11,2.5),E);
 
</asy>
 
 
 
<math>\textbf{(A)}\ 4 \qquad \textbf{(B)}\ 5 \qquad \textbf{(C)}\ 4\sqrt{2} \qquad \textbf{(D)}\ 6 \qquad \textbf{(E)}\ 5\sqrt{2}</math>
 
 
 
[[2024 AMC 8 Problems/Problem 24|Solution]]
 
 
 
==Problem 25==
 
A small airplane has <math>4</math> rows of seats with <math>3</math> seats in each row. Eight passengers have boarded the plane and are distributed randomly among the seats. A married couple is next to board. What is the probability there will be <math>2</math> adjacent seats in the same row for the couple?
 
 
 
[DIAGRAM]
 
 
 
<math>\textbf{(A)}\ \dfrac{8}{15} \qquad \textbf{(B)}\ \dfrac{32}{55} \qquad \textbf{(C)}\ \dfrac{20}{33} \qquad \textbf{(D)}\ \dfrac{34}{55} \qquad \textbf{(E)}\ \dfrac{8}{11}</math>
 
 
 
[[2024 AMC 8 Problems/Problem 25|Solution]]
 
 
 
==See Also==
 
{{AMC8 box|year=2024|before=[[2023 AMC 8 Problems|2023 AMC 8]]|after=[[2025 AMC 8 Problems|2025 AMC 8]]}}
 
* [[AMC 8]]
 
* [[AMC 8 Problems and Solutions]]
 
* [[Mathematics competition resources|Mathematics Competition Resources]]
 

Revision as of 17:57, 2 February 2024

SKIBIDI Toilet Vs. Grimace Shake