Difference between revisions of "2001 AMC 10 Problems"
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− | 1 | + | {{AMC10 Problems|year=2001|ab=}} |
− | + | ==Problem 1== | |
− | |||
− | + | The median of the list <math>n, n + 3, n + 4, n + 5, n + 6, n + 8, n + 10, n + 12, n + 15</math> | |
+ | is <math>10</math>. What is the mean? | ||
− | + | <math>\textbf{(A) } 4 \qquad\textbf{(B) } 6 \qquad\textbf{(C) } 7 \qquad\textbf{(D) } 10 \qquad\textbf{(E) } 11</math> | |
− | (A) | ||
− | (D) | ||
− | + | [[2001 AMC 10 Problems/Problem 1|Solution]] | |
− | |||
− | 4. What is the maximum number for the possible points of intersection of a circle and a triangle? | + | ==Problem 2== |
− | <math>(A) 2 (B) 3 (C) 4 (D) 5 (E) 6</math> | + | A number <math>x</math> is <math>2</math> more than the product of its reciprocal and its additive inverse. In which interval does the number lie? |
+ | |||
+ | <math>\textbf{(A) } -4\leq x\leq -2 \qquad\textbf{(B) } -2<x\leq 0 \qquad\textbf{(C) } 0<x\leq 2 \qquad\textbf{(D) } 2<x\leq 4 \qquad\textbf{(E) } 4<x\leq 6</math> | ||
+ | |||
+ | [[2001 AMC 10 Problems/Problem 2|Solution]] | ||
+ | |||
+ | ==Problem 3== | ||
+ | |||
+ | The sum of two numbers is <math>S</math>. Suppose <math>3</math> is added to each number and then each of the resulting numbers is doubled. What is the sum of the final two numbers? | ||
+ | |||
+ | <math>\textbf{(A) } 2S+3 \qquad\textbf{(B) } 3S+2 \qquad\textbf{(C) } 3S+6 \qquad\textbf{(D) } 2S+6 \qquad\textbf{(E) } 2S+12</math> | ||
+ | |||
+ | [[2001 AMC 12 Problems/Problem 1|Solution]] | ||
+ | |||
+ | ==Problem 4== | ||
+ | |||
+ | What is the maximum number for the possible points of intersection of a circle and a triangle? | ||
+ | |||
+ | <math>\textbf{(A) } 2 \qquad\textbf{(B) } 3 \qquad\textbf{(C) } 4 \qquad\textbf{(D) } 5 \qquad\textbf{(E) } 6</math> | ||
+ | |||
+ | [[2001 AMC 10 Problems/Problem 4|Solution]] | ||
+ | |||
+ | ==Problem 5== | ||
+ | |||
+ | How many of the twelve pentominoes pictured below have at least one line of reflectional symmetry? | ||
+ | |||
+ | <asy> | ||
+ | unitsize(5mm); | ||
+ | defaultpen(linewidth(1pt)); | ||
+ | draw(shift(2,0)*unitsquare); | ||
+ | draw(shift(2,1)*unitsquare); | ||
+ | draw(shift(2,2)*unitsquare); | ||
+ | draw(shift(1,2)*unitsquare); | ||
+ | draw(shift(0,2)*unitsquare); | ||
+ | draw(shift(2,4)*unitsquare); | ||
+ | draw(shift(2,5)*unitsquare); | ||
+ | draw(shift(2,6)*unitsquare); | ||
+ | draw(shift(1,5)*unitsquare); | ||
+ | draw(shift(0,5)*unitsquare); | ||
+ | draw(shift(4,8)*unitsquare); | ||
+ | draw(shift(3,8)*unitsquare); | ||
+ | draw(shift(2,8)*unitsquare); | ||
+ | draw(shift(1,8)*unitsquare); | ||
+ | draw(shift(0,8)*unitsquare); | ||
+ | draw(shift(6,8)*unitsquare); | ||
+ | draw(shift(7,8)*unitsquare); | ||
+ | draw(shift(8,8)*unitsquare); | ||
+ | draw(shift(9,8)*unitsquare); | ||
+ | draw(shift(9,9)*unitsquare); | ||
+ | draw(shift(6,5)*unitsquare); | ||
+ | draw(shift(7,5)*unitsquare); | ||
+ | draw(shift(8,5)*unitsquare); | ||
+ | draw(shift(7,6)*unitsquare); | ||
+ | draw(shift(7,4)*unitsquare); | ||
+ | draw(shift(6,1)*unitsquare); | ||
+ | draw(shift(7,1)*unitsquare); | ||
+ | draw(shift(8,1)*unitsquare); | ||
+ | draw(shift(6,0)*unitsquare); | ||
+ | draw(shift(7,2)*unitsquare); | ||
+ | draw(shift(11,8)*unitsquare); | ||
+ | draw(shift(12,8)*unitsquare); | ||
+ | draw(shift(13,8)*unitsquare); | ||
+ | draw(shift(14,8)*unitsquare); | ||
+ | draw(shift(13,9)*unitsquare); | ||
+ | draw(shift(11,5)*unitsquare); | ||
+ | draw(shift(12,5)*unitsquare); | ||
+ | draw(shift(13,5)*unitsquare); | ||
+ | draw(shift(11,6)*unitsquare); | ||
+ | draw(shift(13,4)*unitsquare); | ||
+ | draw(shift(11,1)*unitsquare); | ||
+ | draw(shift(12,1)*unitsquare); | ||
+ | draw(shift(13,1)*unitsquare); | ||
+ | draw(shift(13,2)*unitsquare); | ||
+ | draw(shift(14,2)*unitsquare); | ||
+ | draw(shift(16,8)*unitsquare); | ||
+ | draw(shift(17,8)*unitsquare); | ||
+ | draw(shift(18,8)*unitsquare); | ||
+ | draw(shift(17,9)*unitsquare); | ||
+ | draw(shift(18,9)*unitsquare); | ||
+ | draw(shift(16,5)*unitsquare); | ||
+ | draw(shift(17,6)*unitsquare); | ||
+ | draw(shift(18,5)*unitsquare); | ||
+ | draw(shift(16,6)*unitsquare); | ||
+ | draw(shift(18,6)*unitsquare); | ||
+ | draw(shift(16,0)*unitsquare); | ||
+ | draw(shift(17,0)*unitsquare); | ||
+ | draw(shift(17,1)*unitsquare); | ||
+ | draw(shift(18,1)*unitsquare); | ||
+ | draw(shift(18,2)*unitsquare);</asy> | ||
+ | |||
+ | <math>\textbf{(A) } 3 \qquad\textbf{(B) } 4 \qquad\textbf{(C) } 5 \qquad\textbf{(D) } 6 \qquad\textbf{(E) } 7</math> | ||
+ | |||
+ | [[2001 AMC 10 Problems/Problem 5|Solution]] | ||
+ | |||
+ | ==Problem 6== | ||
+ | |||
+ | Let <math>P(n)</math> and <math>S(n)</math> denote the product and the sum, respectively, of the digits | ||
+ | of the integer <math>n</math>. For example, <math>P(23) = 6</math> and <math>S(23) = 5</math>. Suppose <math>N</math> is a | ||
+ | two-digit number such that <math>N = P(N)+S(N)</math>. What is the units digit of <math>N</math>? | ||
+ | |||
+ | <math>\textbf{(A) } 2 \qquad\textbf{(B) } 3 \qquad\textbf{(C) } 6 \qquad\textbf{(D) } 8 \qquad\textbf{(E) } 9</math> | ||
+ | |||
+ | [[2001 AMC 12 Problems/Problem 2|Solution]] | ||
+ | |||
+ | ==Problem 7== | ||
+ | |||
+ | When the decimal point of a certain positive decimal number is moved four | ||
+ | places to the right, the new number is four times the reciprocal of the original | ||
+ | number. What is the original number? | ||
+ | |||
+ | <math>\textbf{(A) } 0.0002 \qquad\textbf{(B) } 0.002 \qquad\textbf{(C) } 0.02 \qquad\textbf{(D) } 0.2 \qquad\textbf{(E) } 2</math> | ||
+ | |||
+ | [[2001 AMC 10 Problems/Problem 7|Solution]] | ||
+ | |||
+ | ==Problem 8== | ||
+ | |||
+ | Wanda, Darren, Beatrice, and Chi are tutors in the school math lab. Their | ||
+ | schedule is as follows: Darren works every third school day, Wanda works | ||
+ | every fourth school day, Beatrice works every sixth school day, and Chi works | ||
+ | every seventh school day. Today they are all working in the math lab. In how | ||
+ | many school days from today will they next be together tutoring in the lab? | ||
+ | |||
+ | <math>\textbf{(A) } 42 \qquad\textbf{(B) } 84 \qquad\textbf{(C) } 126 \qquad\textbf{(D) } 178 \qquad\textbf{(E) } 252</math> | ||
+ | |||
+ | [[2001 AMC 10 Problems/Problem 8|Solution]] | ||
+ | |||
+ | == Problem 9 == | ||
+ | |||
+ | The state income tax where Kristin lives is levied at the rate of <math> p\% </math> of the first <math>\textdollar 28000 </math> of annual income plus <math> (p + 2)\% </math> of any amount above <math>\textdollar 28000 </math>. Kristin noticed that the state income tax she paid amounted to <math> (p + 0.25)\% </math> of her annual income. What was her annual income? | ||
+ | |||
+ | <math> \textbf{(A) } \textdollar 28,000\qquad\textbf{(B) } \textdollar 32,000\qquad\textbf{(C) }\textdollar 35,000\qquad\textbf{(D) } \textdollar 42,000\qquad\textbf{(E) } \textdollar 56,000 </math> | ||
+ | |||
+ | [[2001 AMC 10 Problems/Problem 9|Solution]] | ||
+ | |||
+ | == Problem 10 == | ||
+ | |||
+ | If <math>x</math>, <math>y</math>, and <math>z</math> are positive with <math>xy = 24</math>, <math>xz = 48</math>, and <math>yz = 72</math>, then <math>x + y + z</math> is | ||
+ | |||
+ | <math>\textbf{(A) }18\qquad\textbf{(B) }19\qquad\textbf{(C) }20\qquad\textbf{(D) }22\qquad\textbf{(E) }24</math> | ||
+ | |||
+ | [[2001 AMC 10 Problems/Problem 10|Solution]] | ||
+ | |||
+ | == Problem 11 == | ||
+ | |||
+ | Consider the dark square in an array of unit squares, part of which is shown. The first ring of squares around this center square contains <math> 8 </math> unit squares. The second ring contains <math> 16 </math> unit squares. If we continue this process, the number of unit squares in the <math> 100^\text{th} </math> ring is | ||
+ | |||
+ | <asy> | ||
+ | unitsize(3mm); | ||
+ | defaultpen(linewidth(1pt)); | ||
+ | fill((2,2)--(2,7)--(7,7)--(7,2)--cycle, mediumgray); | ||
+ | fill((3,3)--(6,3)--(6,6)--(3,6)--cycle, gray); | ||
+ | fill((4,4)--(5,4)--(5,5)--(4,5)--cycle, black); | ||
+ | for(real i=0; i<=9; ++i) | ||
+ | { | ||
+ | draw((i,0)--(i,9)); | ||
+ | draw((0,i)--(9,i)); | ||
+ | }</asy> | ||
+ | |||
+ | <math>\textbf{(A)}\ 396 \qquad \textbf{(B)}\ 404 \qquad \textbf{(C)}\ 800 \qquad \textbf{(D)}\ 10,\!000 \qquad \textbf{(E)}\ 10,\!404</math> | ||
+ | |||
+ | [[2001 AMC 10 Problems/Problem 11|Solution]] | ||
+ | |||
+ | == Problem 12 == | ||
+ | |||
+ | Suppose that <math> n </math> is the product of three consecutive integers and that <math> n </math> is divisible by <math> 7 </math>. Which of the following is not necessarily a divisor of <math> n </math>? | ||
+ | |||
+ | <math> \textbf{(A)}\ 6 \qquad \textbf{(B)}\ 14 \qquad \textbf{(C)}\ 21 \qquad \textbf{(D)}\ 28 \qquad \textbf{(E)}\ 42 </math> | ||
+ | |||
+ | [[2001 AMC 10 Problems/Problem 12|Solution]] | ||
+ | |||
+ | == Problem 13 == | ||
+ | |||
+ | A telephone number has the form <math> ABC - DEF - GHIJ </math>, where each letter represents a different digit. The digits in each part of the numbers are in decreasing order; that is, <math> A > B > C </math>, <math> D > E > F </math>, and <math> G > H > I > J </math>. Furthermore, <math> D </math>, <math> E </math>, and <math> F </math> are consecutive even digits; <math>G</math>, <math>H</math>, <math>I</math>, and <math>J</math> are consecutive odd digits; and <math>A + B + C = 9</math>. Find <math>A</math>. | ||
+ | |||
+ | <math>\textbf{(A)} \ 4 \qquad \textbf{(B)} \ 5 \qquad \textbf{(C)} \ 6 \qquad \textbf{(D)} \ 7 \qquad \textbf{(E)} \ 8</math> | ||
+ | |||
+ | [[2001 AMC 12 Problems/Problem 6|Solution]] | ||
+ | |||
+ | == Problem 14 == | ||
+ | A charity sells <math>140</math> benefit tickets for a total of <math>\textdollar2001</math>. Some tickets sell for full price (a whole dollar amount), and the rest sells for half price. How much money is raised by the full-price tickets? | ||
+ | |||
+ | <math>\text{(A) } \textdollar 782 \qquad \text{(B) } \textdollar 986 \qquad \text{(C) } \textdollar 1158 \qquad \text{(D) } \textdollar 1219 \qquad \text{(E) }\ \textdollar 1449</math> | ||
+ | |||
+ | [[2001 AMC 12 Problems/Problem 7|Solution]] | ||
+ | |||
+ | == Problem 15 == | ||
+ | |||
+ | A street has parallel curbs <math> 40 </math> feet apart. A crosswalk bounded by two parallel stripes crosses the street at an angle. The length of the curb between the stripes is <math> 15 </math> feet and each stripe is <math> 50 </math> feet long. Find the distance, in feet, between the stripes. | ||
+ | |||
+ | <math> \textbf{(A)}\ 9 \qquad \textbf{(B)}\ 10 \qquad \textbf{(C)}\ 12 \qquad \textbf{(D)}\ 15 \qquad \textbf{(E)}\ 25 </math> | ||
+ | |||
+ | [[2001 AMC 10 Problems/Problem 15|Solution]] | ||
+ | |||
+ | == Problem 16 == | ||
+ | |||
+ | The mean of three numbers is <math> 10 </math> more than the least of the numbers and <math> 15 </math> less than the greatest. The median of the three numbers is <math> 5 </math>. What is their sum? | ||
+ | |||
+ | <math> \textbf{(A)} \ 5 \qquad \textbf{(B)} \ 20 \qquad \textbf{(C)} \ 25 \qquad \textbf{(D)} \ 30 \qquad \textbf{(E)} \ 36 </math> | ||
+ | |||
+ | [[2001 AMC 12 Problems/Problem 4|Solution]] | ||
+ | |||
+ | == Problem 17 == | ||
+ | |||
+ | Which of the cones listed below can be formed from a <math> 252^\circ </math> sector of a circle of radius <math> 10 </math> by aligning the two straight sides? | ||
+ | |||
+ | <asy>import graph;unitsize(1.5cm);defaultpen(fontsize(8pt));draw(Arc((0,0),1,-72,180),linewidth(.8pt));draw(dir(288)--(0,0)--(-1,0),linewidth(.8pt));label("$10$",(-0.5,0),S);draw(Arc((0,0),0.1,-72,180));label("$252^{\circ}$",(0.05,0.05),NE);</asy> | ||
+ | |||
+ | <math> \textbf{(A) } \text{A cone with slant height of 10 and radius 6} </math> | ||
+ | |||
+ | <math> \textbf{(B) } \text{A cone with height of 10 and radius 6} </math> | ||
+ | |||
+ | <math> \textbf{(C) } \text{A cone with slant height of 10 and radius 7} </math> | ||
+ | |||
+ | <math> \textbf{(D) } \text{A cone with height of 10 and radius 7} </math> | ||
+ | |||
+ | <math> \textbf{(E) } \text{A cone with slant height of 10 and radius 8} </math> | ||
+ | |||
+ | |||
+ | [[2001 AMC 12 Problems/Problem 8|Solution]] | ||
+ | |||
+ | == Problem 18 == | ||
+ | |||
+ | The plane is tiled by congruent squares and congruent pentagons as indicated. The percent of the plane that is enclosed by the pentagons is closest to | ||
+ | |||
+ | <asy> | ||
+ | unitsize(3mm); | ||
+ | defaultpen(linewidth(0.8pt)); | ||
+ | path p1=(0,0)--(3,0)--(3,3)--(0,3)--(0,0); | ||
+ | path p2=(0,1)--(1,1)--(1,0); | ||
+ | path p3=(2,0)--(2,1)--(3,1); | ||
+ | path p4=(3,2)--(2,2)--(2,3); | ||
+ | path p5=(1,3)--(1,2)--(0,2); | ||
+ | path p6=(1,1)--(2,2); | ||
+ | path p7=(2,1)--(1,2); | ||
+ | path[] p=p1^^p2^^p3^^p4^^p5^^p6^^p7; | ||
+ | for(int i=0; i<3; ++i) | ||
+ | { | ||
+ | for(int j=0; j<3; ++j) | ||
+ | { | ||
+ | draw(shift(3*i,3*j)*p); | ||
+ | } | ||
+ | }</asy> | ||
+ | |||
+ | <math> \textbf{(A)} \ 50 \qquad \textbf{(B)} \ 52 \qquad \textbf{(C)} \ 54 \qquad \textbf{(D)} \ 56 \qquad \textbf{(E)} \ 58 \qquad </math> | ||
+ | |||
+ | [[2001 AMC 12 Problems/Problem 10|Solution]] | ||
+ | |||
+ | == Problem 19== | ||
+ | |||
+ | Pat wants to buy four donuts from an ample supply of three types of donuts: glazed, chocolate, and powdered. How many different selections are possible? | ||
+ | |||
+ | <math> \textbf{(A)}\ 6 \qquad \textbf{(B)}\ 9 \qquad \textbf{(C)}\ 12 \qquad \textbf{(D)}\ 15 \qquad \textbf{(E)}\ 18 </math> | ||
+ | |||
+ | [[2001 AMC 10 Problems/Problem 19|Solution]] | ||
+ | |||
+ | == Problem 20 == | ||
+ | |||
+ | A regular octagon is formed by cutting an isosceles right triangle from each of the corners of a square with sides of length <math> 2000 </math>. What is the length of each side of the octagon? | ||
+ | |||
+ | <math> \textbf{(A) } \frac{1}{3}(2000) \qquad \textbf{(B) } {2000(\sqrt{2}-1)} \qquad \textbf{(C) } {2000(2-\sqrt{2})} | ||
+ | \qquad \textbf{(D) } {1000} \qquad \textbf{(E) } {1000\sqrt{2}} </math> | ||
+ | |||
+ | [[2001 AMC 10 Problems/Problem 20|Solution]] | ||
+ | |||
+ | == Problem 21 == | ||
+ | |||
+ | A right circular cylinder with its diameter equal to its height is inscribed in a right circular cone. The cone has diameter <math> 10 </math> and altitude <math> 12 </math>, and the axes of the cylinder and cone coincide. Find the radius of the cylinder. | ||
+ | |||
+ | <math> \textbf{(A)}\ \frac{8}3\qquad\textbf{(B)}\ \frac{30}{11}\qquad\textbf{(C)}\ 3\qquad\textbf{(D)}\ \frac{25}{8}\qquad\textbf{(E)}\ \frac{7}{2} </math> | ||
+ | |||
+ | [[2001 AMC 10 Problems/Problem 21|Solution]] | ||
+ | |||
+ | ==Problem 22== | ||
+ | |||
+ | In the magic square shown, the sums of the numbers in each row, column, and diagonal are the same. Five of these numbers are represented by <math> v </math>, <math> w </math>, <math> x </math>, <math> y </math>, and <math> z </math>. Find <math> y + z </math>. | ||
+ | |||
+ | <asy> | ||
+ | unitsize(10mm); | ||
+ | defaultpen(linewidth(1pt)); | ||
+ | for(int i=0; i<=3; ++i) | ||
+ | { | ||
+ | draw((0,i)--(3,i)); | ||
+ | draw((i,0)--(i,3)); | ||
+ | } | ||
+ | label("$25$",(0.5,0.5)); | ||
+ | label("$z$",(1.5,0.5)); | ||
+ | label("$21$",(2.5,0.5)); | ||
+ | label("$18$",(0.5,1.5)); | ||
+ | label("$x$",(1.5,1.5)); | ||
+ | label("$y$",(2.5,1.5)); | ||
+ | label("$v$",(0.5,2.5)); | ||
+ | label("$24$",(1.5,2.5)); | ||
+ | label("$w$",(2.5,2.5)); | ||
+ | |||
+ | </asy> | ||
+ | |||
+ | <math> \textbf{(A)}\ 43 \qquad \textbf{(B)}\ 44 \qquad \textbf{(C)}\ 45 \qquad \textbf{(D)}\ 46 \qquad \textbf{(E)}\ 47 </math> | ||
+ | |||
+ | [[2001 AMC 10 Problems/Problem 22|Solution]] | ||
+ | |||
+ | ==Problem 23== | ||
+ | |||
+ | A box contains exactly five chips, three red and two white. Chips are randomly removed one at a time without replacement until all the red chips are drawn or all the white chips are drawn. What is the probability that the last chip drawn is white? | ||
+ | |||
+ | <math> \textbf{(A)}\ \frac{3}{10}\qquad\textbf{(B)}\ \frac{2}{5}\qquad\textbf{(C)}\ \frac{1}{2}\qquad\textbf{(D)}\ \frac{3}{5}\qquad\textbf{(E)}\ \frac{7}{10} </math> | ||
+ | |||
+ | [[2001 AMC 12 Problems/Problem 11|Solution]] | ||
+ | |||
+ | ==Problem 24== | ||
+ | |||
+ | In trapezoid <math> ABCD </math>, <math> \overline{AB} </math> and <math> \overline{CD} </math> are perpendicular to <math> \overline{AD} </math>, with <math> AB+CD=BC </math>, <math> AB<CD </math>, and <math> AD=7 </math>. What is <math> AB\cdot CD </math>? | ||
+ | |||
+ | <math> \textbf{(A)}\ 12 \qquad \textbf{(B)}\ 12.25 \qquad \textbf{(C)}\ 12.5 \qquad \textbf{(D)}\ 12.75 \qquad \textbf{(E)}\ 13 </math> | ||
+ | |||
+ | [[2001 AMC 10 Problems/Problem 24|Solution]] | ||
+ | |||
+ | ==Problem 25== | ||
+ | |||
+ | How many positive integers not exceeding <math> 2001 </math> are multiples of <math> 3 </math> or <math> 4 </math> but not <math> 5 </math>? | ||
+ | |||
+ | <math> \textbf{(A)}\ 768 \qquad \textbf{(B)}\ 801 \qquad \textbf{(C)}\ 934 \qquad \textbf{(D)}\ 1067 \qquad \textbf{(E)}\ 1167 </math> | ||
+ | |||
+ | [[2001 AMC 12 Problems/Problem 12|Solution]] | ||
+ | |||
+ | == See also == | ||
+ | {{AMC10 box|year=2001|before=[[2000 AMC 10 Problems|2000 AMC 10]]|after=[[2002 AMC 10A Problems|2002 AMC 10A]]}} | ||
+ | * [[AMC 10]] | ||
+ | * [[AMC 10 Problems and Solutions]] | ||
+ | * [[Mathematics competition resources]] | ||
+ | {{MAA Notice}} |
Latest revision as of 16:25, 2 June 2022
2001 AMC 10 (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
The median of the list
is
. What is the mean?
Problem 2
A number is
more than the product of its reciprocal and its additive inverse. In which interval does the number lie?
Problem 3
The sum of two numbers is . Suppose
is added to each number and then each of the resulting numbers is doubled. What is the sum of the final two numbers?
Problem 4
What is the maximum number for the possible points of intersection of a circle and a triangle?
Problem 5
How many of the twelve pentominoes pictured below have at least one line of reflectional symmetry?
Problem 6
Let and
denote the product and the sum, respectively, of the digits
of the integer
. For example,
and
. Suppose
is a
two-digit number such that
. What is the units digit of
?
Problem 7
When the decimal point of a certain positive decimal number is moved four places to the right, the new number is four times the reciprocal of the original number. What is the original number?
Problem 8
Wanda, Darren, Beatrice, and Chi are tutors in the school math lab. Their schedule is as follows: Darren works every third school day, Wanda works every fourth school day, Beatrice works every sixth school day, and Chi works every seventh school day. Today they are all working in the math lab. In how many school days from today will they next be together tutoring in the lab?
Problem 9
The state income tax where Kristin lives is levied at the rate of of the first
of annual income plus
of any amount above
. Kristin noticed that the state income tax she paid amounted to
of her annual income. What was her annual income?
Problem 10
If ,
, and
are positive with
,
, and
, then
is
Problem 11
Consider the dark square in an array of unit squares, part of which is shown. The first ring of squares around this center square contains unit squares. The second ring contains
unit squares. If we continue this process, the number of unit squares in the
ring is
Problem 12
Suppose that is the product of three consecutive integers and that
is divisible by
. Which of the following is not necessarily a divisor of
?
Problem 13
A telephone number has the form , where each letter represents a different digit. The digits in each part of the numbers are in decreasing order; that is,
,
, and
. Furthermore,
,
, and
are consecutive even digits;
,
,
, and
are consecutive odd digits; and
. Find
.
Problem 14
A charity sells benefit tickets for a total of
. Some tickets sell for full price (a whole dollar amount), and the rest sells for half price. How much money is raised by the full-price tickets?
Problem 15
A street has parallel curbs feet apart. A crosswalk bounded by two parallel stripes crosses the street at an angle. The length of the curb between the stripes is
feet and each stripe is
feet long. Find the distance, in feet, between the stripes.
Problem 16
The mean of three numbers is more than the least of the numbers and
less than the greatest. The median of the three numbers is
. What is their sum?
Problem 17
Which of the cones listed below can be formed from a sector of a circle of radius
by aligning the two straight sides?
Problem 18
The plane is tiled by congruent squares and congruent pentagons as indicated. The percent of the plane that is enclosed by the pentagons is closest to
Problem 19
Pat wants to buy four donuts from an ample supply of three types of donuts: glazed, chocolate, and powdered. How many different selections are possible?
Problem 20
A regular octagon is formed by cutting an isosceles right triangle from each of the corners of a square with sides of length . What is the length of each side of the octagon?
Problem 21
A right circular cylinder with its diameter equal to its height is inscribed in a right circular cone. The cone has diameter and altitude
, and the axes of the cylinder and cone coincide. Find the radius of the cylinder.
Problem 22
In the magic square shown, the sums of the numbers in each row, column, and diagonal are the same. Five of these numbers are represented by ,
,
,
, and
. Find
.
Problem 23
A box contains exactly five chips, three red and two white. Chips are randomly removed one at a time without replacement until all the red chips are drawn or all the white chips are drawn. What is the probability that the last chip drawn is white?
Problem 24
In trapezoid ,
and
are perpendicular to
, with
,
, and
. What is
?
Problem 25
How many positive integers not exceeding are multiples of
or
but not
?
See also
2001 AMC 10 (Problems • Answer Key • Resources) | ||
Preceded by 2000 AMC 10 |
Followed by 2002 AMC 10A | |
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 | ||
All AMC 10 Problems and Solutions |
The problems on this page are copyrighted by the Mathematical Association of America's American Mathematics Competitions.