Difference between revisions of "2022 AMC 10A Problems"
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==Problem 7== | ==Problem 7== | ||
− | The least common multiple of a positive | + | The least common multiple of a positive integer <math>n</math> and <math>18</math> is <math>180</math>, and the greatest common divisor of <math>n</math> and <math>45</math> is <math>15</math>. What is the sum of the digits of <math>n</math>? |
<math>\textbf{(A) } 3 \qquad \textbf{(B) } 6 \qquad \textbf{(C) } 8 \qquad \textbf{(D) } 9 \qquad \textbf{(E) } 12</math> | <math>\textbf{(A) } 3 \qquad \textbf{(B) } 6 \qquad \textbf{(C) } 8 \qquad \textbf{(D) } 9 \qquad \textbf{(E) } 12</math> | ||
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==Problem 8== | ==Problem 8== | ||
− | A data set consists of <math>6</math> not distinct) positive integers: <math>1</math>, <math>7</math>, <math>5</math>, <math>2</math>, <math>5</math>, and <math>X</math>. The | + | A data set consists of <math>6</math> (not distinct) positive integers: <math>1</math>, <math>7</math>, <math>5</math>, <math>2</math>, <math>5</math>, and <math>X</math>. The average (arithmetic mean) of the <math>6</math> numbers equals a value in the data set. What is the sum of all possible values of <math>X</math>? |
− | average (arithmetic mean) of the <math>6</math> numbers equals a value in the data set. What is | ||
− | the sum of all | ||
<math>\textbf{(A) } 10 \qquad \textbf{(B) } 26 \qquad \textbf{(C) } 32 \qquad \textbf{(D) } 36 \qquad \textbf{(E) } 40</math> | <math>\textbf{(A) } 10 \qquad \textbf{(B) } 26 \qquad \textbf{(C) } 32 \qquad \textbf{(D) } 36 \qquad \textbf{(E) } 40</math> | ||
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==Problem 9== | ==Problem 9== | ||
− | + | A rectangle is partitioned into <math>5</math> regions as shown. Each region is to be painted a solid color - red, orange, yellow, blue, or green - so that regions that touch are painted different colors, and colors can be used more than once. How many different colorings are possible? | |
− | <math>\textbf{(A) } | + | <asy> size(5.5cm); draw((0,0)--(0,2)--(2,2)--(2,0)--cycle); draw((2,0)--(8,0)--(8,2)--(2,2)--cycle); draw((8,0)--(12,0)--(12,2)--(8,2)--cycle); draw((0,2)--(6,2)--(6,4)--(0,4)--cycle); draw((6,2)--(12,2)--(12,4)--(6,4)--cycle); </asy> |
+ | |||
+ | <math>\textbf{(A) }120\qquad\textbf{(B) }270\qquad\textbf{(C) }360\qquad\textbf{(D) }540\qquad\textbf{(E) }720</math> | ||
[[2022 AMC 10A Problems/Problem 9|Solution]] | [[2022 AMC 10A Problems/Problem 9|Solution]] | ||
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==Problem 10== | ==Problem 10== | ||
− | + | Daniel finds a rectangular index card and measures its diagonal to be <math>8</math> centimeters. | |
− | + | Daniel then cuts out equal squares of side <math>1</math> cm at two opposite corners of the index card and measures the distance between the two closest vertices of these squares to be <math>4\sqrt{2}</math> centimeters, as shown below. What is the area of the original index card? | |
− | <math>\textbf{(A) } | + | <asy> |
+ | // Diagram by MRENTHUSIASM, edited by Djmathman | ||
+ | size(200); | ||
+ | defaultpen(linewidth(0.6)); | ||
+ | draw((489.5,-213) -- (225.5,-213) -- (225.5,-185) -- (199.5,-185) -- (198.5,-62) -- (457.5,-62) -- (457.5,-93) -- (489.5,-93) -- cycle); | ||
+ | draw((206.29,-70.89) -- (480.21,-207.11), linetype ("6 6"),Arrows(size=4,arrowhead=HookHead)); | ||
+ | draw((237.85,-182.24) -- (448.65,-95.76),linetype ("6 6"),Arrows(size=4,arrowhead=HookHead)); | ||
+ | label("$1$",(450,-80)); | ||
+ | label("$1$",(475,-106)); | ||
+ | label("$8$",(300,-103)); | ||
+ | label("$4\sqrt 2$",(300,-173)); | ||
+ | </asy> | ||
+ | <math>\textbf{(A) } 14 \qquad \textbf{(B) } 10\sqrt{2} \qquad \textbf{(C) } 16 \qquad \textbf{(D) } 12\sqrt{2} \qquad \textbf{(E) } 18</math> | ||
[[2022 AMC 10A Problems/Problem 10|Solution]] | [[2022 AMC 10A Problems/Problem 10|Solution]] | ||
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==Problem 11== | ==Problem 11== | ||
− | + | Ted mistakenly wrote <math>2^m\cdot\sqrt{\frac{1}{4096}}</math> as <math>2\cdot\sqrt[m]{\frac{1}{4096}}.</math> What is the sum of all real numbers <math>m</math> for which these two expressions have the same value? | |
− | <math>\textbf{(A) } | + | <math>\textbf{(A) } 5 \qquad \textbf{(B) } 6 \qquad \textbf{(C) } 7 \qquad \textbf{(D) } 8 \qquad \textbf{(E) } 9</math> |
[[2022 AMC 10A Problems/Problem 11|Solution]] | [[2022 AMC 10A Problems/Problem 11|Solution]] | ||
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==Problem 12== | ==Problem 12== | ||
− | On Halloween <math>31</math> children walked into the principal's office asking for candy. They | + | On Halloween, <math>31</math> children walked into the principal's office asking for candy. They |
can be classified into three types: Some always lie; some always tell the truth; and | can be classified into three types: Some always lie; some always tell the truth; and | ||
some alternately lie and tell the truth. The alternaters arbitrarily choose their first | some alternately lie and tell the truth. The alternaters arbitrarily choose their first | ||
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==Problem 13== | ==Problem 13== | ||
− | + | Let <math>\triangle ABC</math> be a scalene triangle. Point <math>P</math> lies on <math>\overline{BC}</math> so that <math>\overline{AP}</math> bisects <math>\angle BAC.</math> The line through <math>B</math> perpendicular to <math>\overline{AP}</math> intersects the line through <math>A</math> parallel to <math>\overline{BC}</math> at point <math>D.</math> Suppose <math>BP=2</math> and <math>PC=3.</math> What is <math>AD?</math> | |
− | <math>\textbf{(A) } | + | <math>\textbf{(A) } 8 \qquad \textbf{(B) } 9 \qquad \textbf{(C) } 10 \qquad \textbf{(D) } 11 \qquad \textbf{(E) } 12</math> |
[[2022 AMC 10A Problems/Problem 13|Solution]] | [[2022 AMC 10A Problems/Problem 13|Solution]] | ||
Line 125: | Line 137: | ||
==Problem 14== | ==Problem 14== | ||
− | + | How many ways are there to split the integers <math>1</math> through <math>14</math> into <math>7</math> pairs such that in each pair, the greater number is at least <math>2</math> times the lesser number? | |
− | <math>\textbf{(A) } | + | <math>\textbf{(A) } 108 \qquad \textbf{(B) } 120 \qquad \textbf{(C) } 126 \qquad \textbf{(D) } 132 \qquad \textbf{(E) } 144</math> |
[[2022 AMC 10A Problems/Problem 14|Solution]] | [[2022 AMC 10A Problems/Problem 14|Solution]] | ||
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==Problem 15== | ==Problem 15== | ||
− | + | Quadrilateral <math>ABCD</math> with side lengths <math>AB=7, BC=24, CD=20, DA=15</math> is inscribed in a circle. The area interior to the circle but exterior to the quadrilateral can be written in the form <math>\frac{a\pi-b}{c},</math> where <math>a,b,</math> and <math>c</math> are positive integers such that <math>a</math> and <math>c</math> have no common prime factor. What is <math>a+b+c?</math> | |
− | <math>\textbf{(A) } | + | <math>\textbf{(A) } 260 \qquad \textbf{(B) } 855 \qquad \textbf{(C) } 1235 \qquad \textbf{(D) } 1565 \qquad \textbf{(E) } 1997</math> |
[[2022 AMC 10A Problems/Problem 15|Solution]] | [[2022 AMC 10A Problems/Problem 15|Solution]] | ||
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==Problem 16== | ==Problem 16== | ||
− | + | The roots of the polynomial <math>10x^3 - 39x^2 + 29x - 6</math> are the height, length, and width of a rectangular box (right rectangular prism). A new rectangular box is formed by lengthening each edge of the original box by <math>2</math> units. What is the volume of the new box? | |
− | <math>\textbf{(A) } | + | <math>\textbf{(A) } \frac{24}{5} \qquad \textbf{(B) } \frac{42}{5} \qquad \textbf{(C) } \frac{81}{5} \qquad \textbf{(D) } 30 \qquad \textbf{(E) } 48</math> |
[[2022 AMC 10A Problems/Problem 16|Solution]] | [[2022 AMC 10A Problems/Problem 16|Solution]] | ||
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==Problem 17== | ==Problem 17== | ||
− | + | How many three-digit positive integers <math>\underline{a} \ \underline{b} \ \underline{c}</math> are there whose nonzero digits <math>a,b,</math> and <math>c</math> satisfy | |
+ | <cmath>0.\overline{\underline{a}~\underline{b}~\underline{c}} = \frac{1}{3} (0.\overline{a} + 0.\overline{b} + 0.\overline{c})?</cmath> | ||
+ | (The bar indicates repetition, thus <math>0.\overline{\underline{a}~\underline{b}~\underline{c}}</math> is the infinite repeating decimal <math>0.\underline{a}~\underline{b}~\underline{c}~\underline{a}~\underline{b}~\underline{c}~\cdots</math>) | ||
− | <math>\textbf{(A) } | + | <math>\textbf{(A) } 9 \qquad \textbf{(B) } 10 \qquad \textbf{(C) } 11 \qquad \textbf{(D) } 13 \qquad \textbf{(E) } 14</math> |
[[2022 AMC 10A Problems/Problem 17|Solution]] | [[2022 AMC 10A Problems/Problem 17|Solution]] | ||
==Problem 18== | ==Problem 18== | ||
+ | Let <math>T_k</math> be the transformation of the coordinate plane that first rotates the plane <math>k</math> degrees counterclockwise around the origin and then reflects the plane across the <math>y</math>-axis. What is the least positive integer <math>n</math> such that performing the sequence of transformations <math>T_1, T_2, T_3,...,T_n</math> returns the point <math>(1, 0)</math> back to itself? | ||
− | + | <math>\textbf{(A) } 359 \qquad \textbf{(B) } 360 \qquad \textbf{(C) } 719 \qquad \textbf{(D) } 720 \qquad \textbf{(E) } 721 </math> | |
− | |||
− | <math>\textbf{(A) } | ||
[[2022 AMC 10A Problems/Problem 18|Solution]] | [[2022 AMC 10A Problems/Problem 18|Solution]] | ||
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==Problem 19== | ==Problem 19== | ||
− | + | Define <math>L_n</math> as the least common multiple of all the integers from <math>1</math> to <math>n</math> inclusive. There is a unique integer <math>h</math> such that | |
+ | <cmath>\frac{1}{1}+\frac{1}{2}+\frac{1}{3}+\cdots+\frac{1}{17}=\frac{h}{L_{17}}</cmath> | ||
+ | What is the remainder when <math>h</math> is divided by <math>17</math>? | ||
− | <math>\textbf{(A) } | + | <math>\textbf{(A) } 1 \qquad \textbf{(B) } 3 \qquad \textbf{(C) } 5 \qquad \textbf{(D) } 7 \qquad \textbf{(E) } 9</math> |
[[2022 AMC 10A Problems/Problem 19|Solution]] | [[2022 AMC 10A Problems/Problem 19|Solution]] | ||
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A four-term sequence is formed by adding each term of a four-term arithmetic sequence of positive integers to the corresponding term of a four-term geometric sequence of positive integers. The first three terms of the resulting four-term sequence are <math>57</math>, <math>60</math>, and <math>91</math>. What is the fourth term of this sequence? | A four-term sequence is formed by adding each term of a four-term arithmetic sequence of positive integers to the corresponding term of a four-term geometric sequence of positive integers. The first three terms of the resulting four-term sequence are <math>57</math>, <math>60</math>, and <math>91</math>. What is the fourth term of this sequence? | ||
− | <math>\textbf{(A) } | + | <math>\textbf{(A) } 190 \qquad \textbf{(B) } 194 \qquad \textbf{(C) } 198 \qquad \textbf{(D) } 202 \qquad \textbf{(E) } 206</math> |
[[2022 AMC 10A Problems/Problem 20|Solution]] | [[2022 AMC 10A Problems/Problem 20|Solution]] | ||
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==Problem 21== | ==Problem 21== | ||
− | A bowl is formed by attaching four regular hexagons of side 1 to a square of side 1. The edges of the adjacent hexagons coincide, as shown in the figure. What is the area of the octagon obtained by joining the top eight vertices of the four hexagons, situated on the rim of the bowl? | + | A bowl is formed by attaching four regular hexagons of side <math>1</math> to a square of side <math>1</math>. The edges of the adjacent hexagons coincide, as shown in the figure. What is the area of the octagon obtained by joining the top eight vertices of the four hexagons, situated on the rim of the bowl? |
+ | <asy> | ||
+ | import three; | ||
+ | size(225); | ||
+ | currentprojection= | ||
+ | orthographic(camera=(-5.52541796301147,-2.61548797564715,1.6545450372312), | ||
+ | up=(0.00247902062334861,0.000877141782387748,0.00966536329192992), | ||
+ | target=(0,0,0), | ||
+ | zoom=0.570588560870951); | ||
+ | currentpen = black+1.5bp; | ||
+ | triple A = O; | ||
+ | triple M = (X+Y)/2; | ||
+ | triple B = (-1/2,-1/2,1/sqrt(2)); | ||
+ | triple C = (-1,0,sqrt(2)); | ||
+ | triple D = (0,-1,sqrt(2)); | ||
+ | transform3 rho = rotate(90,M,M+Z); | ||
+ | |||
+ | //arrays of vertices for the lower level (the square), the middle level, | ||
+ | //and the interleaves vertices of the upper level (the octagon) | ||
+ | triple[] lVs = {A}; | ||
+ | triple[] mVs = {B}; | ||
+ | triple[] uVsl = {C}; | ||
+ | triple[] uVsr = {D}; | ||
+ | |||
+ | for(int i = 0; i < 3; ++i){ | ||
+ | lVs.push(rho*lVs[i]); | ||
+ | mVs.push(rho*mVs[i]); | ||
+ | uVsl.push(rho*uVsl[i]); | ||
+ | uVsr.push(rho*uVsr[i]); | ||
+ | } | ||
+ | |||
+ | lVs.cyclic = true; | ||
+ | uVsl.cyclic = true; | ||
+ | |||
+ | for(int i : new int[] {0,1,2,3}){ | ||
+ | draw(uVsl[i]--uVsr[i]); | ||
+ | draw(uVsr[i]--uVsl[i+1]); | ||
+ | } | ||
+ | draw(lVs[0]--lVs[1]^^lVs[0]--lVs[3]); | ||
+ | for(int i : new int[] {0,1,3}){ | ||
+ | draw(lVs[0]--lVs[i]); | ||
+ | draw(lVs[i]--mVs[i]); | ||
+ | draw(mVs[i]--uVsl[i]); | ||
+ | } | ||
+ | for(int i : new int[] {0,3}){ | ||
+ | draw(mVs[i]--uVsr[i]); | ||
+ | } | ||
+ | |||
+ | for(int i : new int[] {1,3}) draw(lVs[2]--lVs[i],dashed); | ||
+ | draw(lVs[2]--mVs[2],dashed); | ||
+ | draw(mVs[2]--uVsl[2]^^mVs[2]--uVsr[2],dashed); | ||
+ | draw(mVs[1]--uVsr[1],dashed); | ||
− | <math>\textbf{(A) } | + | //Comment two lines below to remove red edges |
+ | //draw(lVs[1]--lVs[3],red+2bp); | ||
+ | //draw(uVsl[0]--uVsr[0],red+2bp); | ||
+ | </asy> | ||
+ | <math>\textbf{(A) } 6 \qquad \textbf{(B) } 7 \qquad \textbf{(C) } 5+2\sqrt{2} \qquad \textbf{(D) } 8 \qquad \textbf{(E) } 9</math> | ||
[[2022 AMC 10A Problems/Problem 21|Solution]] | [[2022 AMC 10A Problems/Problem 21|Solution]] | ||
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==Problem 22== | ==Problem 22== | ||
− | + | Suppose that <math>13</math> cards numbered <math>1, 2, 3, \ldots, 13</math> are arranged in a row. The task is to pick them up in numerically increasing order, working repeatedly from left to right. In the example below, cards <math>1, 2, 3</math> are picked up on the first pass, <math>4</math> and <math>5</math> on the second pass, <math>6</math> on the third pass, <math>7, 8, 9, 10</math> on the fourth pass, and <math>11, 12, 13</math> on the fifth pass. For how many of the <math>13!</math> possible orderings of the cards will the <math>13</math> cards be picked up in exactly two passes? | |
− | <math>\textbf{(A) } | + | <asy> |
+ | size(11cm); | ||
+ | draw((0,0)--(2,0)--(2,3)--(0,3)--cycle); | ||
+ | label("7", (1,1.5)); | ||
+ | draw((3,0)--(5,0)--(5,3)--(3,3)--cycle); | ||
+ | label("11", (4,1.5)); | ||
+ | draw((6,0)--(8,0)--(8,3)--(6,3)--cycle); | ||
+ | label("8", (7,1.5)); | ||
+ | draw((9,0)--(11,0)--(11,3)--(9,3)--cycle); | ||
+ | label("6", (10,1.5)); | ||
+ | draw((12,0)--(14,0)--(14,3)--(12,3)--cycle); | ||
+ | label("4", (13,1.5)); | ||
+ | draw((15,0)--(17,0)--(17,3)--(15,3)--cycle); | ||
+ | label("5", (16,1.5)); | ||
+ | draw((18,0)--(20,0)--(20,3)--(18,3)--cycle); | ||
+ | label("9", (19,1.5)); | ||
+ | draw((21,0)--(23,0)--(23,3)--(21,3)--cycle); | ||
+ | label("12", (22,1.5)); | ||
+ | draw((24,0)--(26,0)--(26,3)--(24,3)--cycle); | ||
+ | label("1", (25,1.5)); | ||
+ | draw((27,0)--(29,0)--(29,3)--(27,3)--cycle); | ||
+ | label("13", (28,1.5)); | ||
+ | draw((30,0)--(32,0)--(32,3)--(30,3)--cycle); | ||
+ | label("10", (31,1.5)); | ||
+ | draw((33,0)--(35,0)--(35,3)--(33,3)--cycle); | ||
+ | label("2", (34,1.5)); | ||
+ | draw((36,0)--(38,0)--(38,3)--(36,3)--cycle); | ||
+ | label("3", (37,1.5)); | ||
+ | </asy> | ||
+ | <math>\textbf{(A) } 4082 \qquad \textbf{(B) } 4095 \qquad \textbf{(C) } 4096 \qquad \textbf{(D) } 8178 \qquad \textbf{(E) } 8191</math> | ||
[[2022 AMC 10A Problems/Problem 22|Solution]] | [[2022 AMC 10A Problems/Problem 22|Solution]] | ||
Line 198: | Line 297: | ||
==Problem 23== | ==Problem 23== | ||
− | + | Isosceles trapezoid <math>ABCD</math> has parallel sides <math>\overline{AD}</math> and <math>\overline{BC},</math> with <math>BC < AD</math> and <math>AB = CD.</math> There is a point <math>P</math> in the plane such that <math>PA=1, PB=2, PC=3,</math> and <math>PD=4.</math> What is <math>\tfrac{BC}{AD}?</math> | |
− | <math>\textbf{(A) } | + | <math>\textbf{(A) }\frac{1}{4}\qquad\textbf{(B) }\frac{1}{3}\qquad\textbf{(C) }\frac{1}{2}\qquad\textbf{(D) }\frac{2}{3}\qquad\textbf{(E) }\frac{3}{4}</math> |
[[2022 AMC 10A Problems/Problem 23|Solution]] | [[2022 AMC 10A Problems/Problem 23|Solution]] | ||
Line 206: | Line 305: | ||
==Problem 24== | ==Problem 24== | ||
− | + | How many strings of length <math>5</math> formed from the digits <math>0</math>, <math>1</math>, <math>2</math>, <math>3</math>, <math>4</math> are there such that for each <math>j \in \{1,2,3,4\}</math>, at least <math>j</math> of the digits are less than <math>j</math>? (For example, <math>02214</math> satisfies this condition | |
+ | because it contains at least <math>1</math> digit less than <math>1</math>, at least <math>2</math> digits less than <math>2</math>, at least <math>3</math> digits less | ||
+ | than <math>3</math>, and at least <math>4</math> digits less than <math>4</math>. The string <math>23404</math> does not satisfy the condition because it | ||
+ | does not contain at least <math>2</math> digits less than <math>2</math>.) | ||
− | <math>\textbf{(A) } | + | <math>\textbf{(A) }500\qquad\textbf{(B) }625\qquad\textbf{(C) }1089\qquad\textbf{(D) }1199\qquad\textbf{(E) }1296</math> |
[[2022 AMC 10A Problems/Problem 24|Solution]] | [[2022 AMC 10A Problems/Problem 24|Solution]] | ||
Line 214: | Line 316: | ||
==Problem 25== | ==Problem 25== | ||
− | + | Let <math>R</math>, <math>S</math>, and <math>T</math> be squares that have vertices at lattice points (i.e., points whose coordinates are both integers) in the coordinate plane, together with their interiors. The bottom edge of each square is on the <math>x</math>-axis. The left edge of <math>R</math> and the right edge of <math>S</math> are on the <math>y</math>-axis, and <math>R</math> contains <math>\frac{9}{4}</math> as many lattice points as does <math>S</math>. The top two vertices of <math>T</math> are in <math>R \cup S</math>, and <math>T</math> contains <math>\frac{1}{4}</math> of the lattice points contained in <math>R \cup S.</math> See the figure (not drawn to scale). | |
+ | <asy> | ||
+ | size(8cm); | ||
+ | label(scale(.8)*"$y$", (0,60), N); | ||
+ | label(scale(.8)*"$x$", (60,0), E); | ||
+ | filldraw((0,0)--(55,0)--(55,55)--(0,55)--cycle, yellow+orange+white+white); | ||
+ | label(scale(1.3)*"$R$", (55/2,55/2)); | ||
+ | filldraw((0,0)--(0,28)--(-28,28)--(-28,0)--cycle, green+white+white); | ||
+ | label(scale(1.3)*"$S$",(-14,14)); | ||
+ | filldraw((-10,0)--(15,0)--(15,25)--(-10,25)--cycle, red+white+white); | ||
+ | label(scale(1.3)*"$T$",(3.5,25/2)); | ||
+ | draw((0,-10)--(0,60),EndArrow()); | ||
+ | draw((-34,0)--(60,0),EndArrow()); | ||
+ | </asy> | ||
+ | The fraction of lattice points in <math>S</math> that are in <math>S \cap T</math> is <math>27</math> times the fraction of lattice points in <math>R</math> that are in <math>R \cap T</math>. What is the minimum possible value of the edge length of <math>R</math> plus the edge length of <math>S</math> plus the edge length of <math>T</math>? | ||
− | <math>\textbf{(A) } | + | <math>\textbf{(A) }336\qquad\textbf{(B) }337\qquad\textbf{(C) }338\qquad\textbf{(D) }339\qquad\textbf{(E) }340</math> |
[[2022 AMC 10A Problems/Problem 25|Solution]] | [[2022 AMC 10A Problems/Problem 25|Solution]] | ||
==See also== | ==See also== | ||
− | {{AMC10 box|year= | + | {{AMC10 box|year=2022|ab=A|before=[[2021 Fall AMC 10B Problems]]|after=[[2022 AMC 10B Problems]]}} |
{{MAA Notice}} | {{MAA Notice}} |
Latest revision as of 18:03, 3 November 2024
2022 AMC 10A (Answer Key) Printable versions: • AoPS Resources • PDF | ||
Instructions
| ||
1 • 2 • 3 • 4 • 5 • 6 • 7 • 8 • 9 • 10 • 11 • 12 • 13 • 14 • 15 • 16 • 17 • 18 • 19 • 20 • 21 • 22 • 23 • 24 • 25 |
Contents
- 1 Problem 1
- 2 Problem 2
- 3 Problem 3
- 4 Problem 4
- 5 Problem 5
- 6 Problem 6
- 7 Problem 7
- 8 Problem 8
- 9 Problem 9
- 10 Problem 10
- 11 Problem 11
- 12 Problem 12
- 13 Problem 13
- 14 Problem 14
- 15 Problem 15
- 16 Problem 16
- 17 Problem 17
- 18 Problem 18
- 19 Problem 19
- 20 Problem 20
- 21 Problem 21
- 22 Problem 22
- 23 Problem 23
- 24 Problem 24
- 25 Problem 25
- 26 See also
Problem 1
What is the value of
Problem 2
Mike cycled laps in minutes. Assume he cycled at a constant speed throughout. Approximately how many laps did he complete in the first minutes?
Problem 3
The sum of three numbers is The first number is times the third number, and the third number is less than the second number. What is the absolute value of the difference between the first and second numbers?
Problem 4
In some countries, automobile fuel efficiency is measured in liters per kilometers while other countries use miles per gallon. Suppose that 1 kilometer equals miles, and gallon equals liters. Which of the following gives the fuel efficiency in liters per kilometers for a car that gets miles per gallon?
Problem 5
Square has side length . Points , , , and each lie on a side of such that is an equilateral convex hexagon with side length . What is ?
Problem 6
Which expression is equal to for
Problem 7
The least common multiple of a positive integer and is , and the greatest common divisor of and is . What is the sum of the digits of ?
Problem 8
A data set consists of (not distinct) positive integers: , , , , , and . The average (arithmetic mean) of the numbers equals a value in the data set. What is the sum of all possible values of ?
Problem 9
A rectangle is partitioned into regions as shown. Each region is to be painted a solid color - red, orange, yellow, blue, or green - so that regions that touch are painted different colors, and colors can be used more than once. How many different colorings are possible?
Problem 10
Daniel finds a rectangular index card and measures its diagonal to be centimeters. Daniel then cuts out equal squares of side cm at two opposite corners of the index card and measures the distance between the two closest vertices of these squares to be centimeters, as shown below. What is the area of the original index card?
Problem 11
Ted mistakenly wrote as What is the sum of all real numbers for which these two expressions have the same value?
Problem 12
On Halloween, children walked into the principal's office asking for candy. They can be classified into three types: Some always lie; some always tell the truth; and some alternately lie and tell the truth. The alternaters arbitrarily choose their first response, either a lie or the truth, but each subsequent statement has the opposite truth value from its predecessor. The principal asked everyone the same three questions in this order.
"Are you a truth-teller?" The principal gave a piece of candy to each of the children who answered yes.
"Are you an alternater?" The principal gave a piece of candy to each of the children who answered yes.
"Are you a liar?" The principal gave a piece of candy to each of the children who answered yes.
How many pieces of candy in all did the principal give to the children who always tell the truth?
Problem 13
Let be a scalene triangle. Point lies on so that bisects The line through perpendicular to intersects the line through parallel to at point Suppose and What is
Problem 14
How many ways are there to split the integers through into pairs such that in each pair, the greater number is at least times the lesser number?
Problem 15
Quadrilateral with side lengths is inscribed in a circle. The area interior to the circle but exterior to the quadrilateral can be written in the form where and are positive integers such that and have no common prime factor. What is
Problem 16
The roots of the polynomial are the height, length, and width of a rectangular box (right rectangular prism). A new rectangular box is formed by lengthening each edge of the original box by units. What is the volume of the new box?
Problem 17
How many three-digit positive integers are there whose nonzero digits and satisfy (The bar indicates repetition, thus is the infinite repeating decimal )
Problem 18
Let be the transformation of the coordinate plane that first rotates the plane degrees counterclockwise around the origin and then reflects the plane across the -axis. What is the least positive integer such that performing the sequence of transformations returns the point back to itself?
Problem 19
Define as the least common multiple of all the integers from to inclusive. There is a unique integer such that What is the remainder when is divided by ?
Problem 20
A four-term sequence is formed by adding each term of a four-term arithmetic sequence of positive integers to the corresponding term of a four-term geometric sequence of positive integers. The first three terms of the resulting four-term sequence are , , and . What is the fourth term of this sequence?
Problem 21
A bowl is formed by attaching four regular hexagons of side to a square of side . The edges of the adjacent hexagons coincide, as shown in the figure. What is the area of the octagon obtained by joining the top eight vertices of the four hexagons, situated on the rim of the bowl?
Problem 22
Suppose that cards numbered are arranged in a row. The task is to pick them up in numerically increasing order, working repeatedly from left to right. In the example below, cards are picked up on the first pass, and on the second pass, on the third pass, on the fourth pass, and on the fifth pass. For how many of the possible orderings of the cards will the cards be picked up in exactly two passes?
Problem 23
Isosceles trapezoid has parallel sides and with and There is a point in the plane such that and What is
Problem 24
How many strings of length formed from the digits , , , , are there such that for each , at least of the digits are less than ? (For example, satisfies this condition because it contains at least digit less than , at least digits less than , at least digits less than , and at least digits less than . The string does not satisfy the condition because it does not contain at least digits less than .)
Problem 25
Let , , and be squares that have vertices at lattice points (i.e., points whose coordinates are both integers) in the coordinate plane, together with their interiors. The bottom edge of each square is on the -axis. The left edge of and the right edge of are on the -axis, and contains as many lattice points as does . The top two vertices of are in , and contains of the lattice points contained in See the figure (not drawn to scale). The fraction of lattice points in that are in is times the fraction of lattice points in that are in . What is the minimum possible value of the edge length of plus the edge length of plus the edge length of ?
See also
2022 AMC 10A (Problems • Answer Key • Resources) | ||
Preceded by 2021 Fall AMC 10B Problems |
Followed by 2022 AMC 10B Problems | |
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