Difference between revisions of "1982 AHSME Problems"

Latest revision as of 18:05, 11 September 2023

1982 AHSME (Answer Key) Printable versions: Wiki • AoPS Resources • PDF
Instructions This is a 30-question, multiple choice test. Each question is followed by answers marked A, B, C, D and E. Only one of these is correct. You will receive 5 points for each correct answer, 2 points for each problem left unanswered, and 0 points for each incorrect answer. No aids are permitted other than scratch paper, graph paper, ruler, compass, protractor and erasers. Figures are not necessarily drawn to scale. You will have 90 minutes working time to complete the test.
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Problem 1

When the polynomial $x^3-2$ is divided by the polynomial $x^2-2$ , the remainder is

$\textbf{(A)} \ 2 \qquad \textbf{(B)} \ -2 \qquad \textbf{(C)} \ -2x-2 \qquad \textbf{(D)} \ 2x+2 \qquad \textbf{(E)} \ 2x-2$

Solution

Problem 2

If a number eight times as large as $x$ is increased by two, then one fourth of the result equals

$\textbf{(A)} \ 2x + \frac{1}{2} \qquad \textbf{(B)} \ x + \frac{1}{2} \qquad \textbf{(C)} \ 2x+2 \qquad \textbf{(D)}\ 2x+4 \qquad \textbf{(E)}\ 2x+16$

Solution

Problem 3

Evaluate $(x^x)^{(x^x)}$ at $x = 2$ .

$\textbf{(A)} \ 16 \qquad \textbf{(B)} \ 64 \qquad \textbf{(C)} \ 256 \qquad \textbf{(D)} \ 1024 \qquad \textbf{(E)} \ 65,536$

Solution

Problem 4

The perimeter of a semicircular region, measured in centimeters, is numerically equal to its area, measured in square centimeters. The radius of the semicircle, measured in centimeters, is

$\textbf{(A)} \ \pi \qquad \textbf{(B)} \ \frac{2}{\pi} \qquad \textbf{(C)} \ 1 \qquad \textbf{(D)} \ \frac{1}{2}\qquad \textbf{(E)} \ \frac{4}{\pi}+2$

Solution

Problem 5

Two positive numbers $x$ and $y$ are in the ratio $a: b$ where $0 < a < b$ . If $x+y = c$ , then the smaller of $x$ and $y$ is

$\textbf{(A)} \ \frac{ac}{b} \qquad \textbf{(B)} \ \frac{bc-ac}{b} \qquad \textbf{(C)} \ \frac{ac}{a+b} \qquad \textbf{(D)}\ \frac{bc}{a+b}\qquad \textbf{(E)}\ \frac{ac}{b-a}$

Solution

Problem 6

The sum of all but one of the interior angles of a convex polygon equals $2570^\circ$ . The remaining angle is

$\textbf{(A)} \ 90^\circ \qquad \textbf{(B)} \ 105^\circ \qquad \textbf{(C)} \ 120^\circ \qquad \textbf{(D)}\ 130^\circ\qquad \textbf{(E)}\ 144^\circ$

Solution

Problem 7

If the operation $x \star y$ is defined by $x \star y = (x+1)(y+1) - 1$ , then which one of the following is FALSE?

$\textbf{(A)} \ x \star y = y\star x \text{ for all real } x,y. \\ \textbf{(B)} \ x \star (y + z) = ( x \star y ) + (x \star z) \text{ for all real } x,y, \text{ and } z.\\ \textbf{(C)} \ (x-1) \star (x+1) = (x \star x) - 1 \text{ for all real } x. \\ \textbf{(D)} \ x \star 0 = x \text{ for all real } x. \\ \textbf{(E)} \ x \star (y \star z) = (x \star y) \star z \text{ for all real } x,y, \text{ and } z.$

Solution

Problem 8

By definition, $r! = r(r - 1) \cdots 1$ and $\binom{j}{k} = \frac {j!}{k!(j - k)!}$ , where $r,j,k$ are positive integers and $k < j$ . If $\binom{n}{1}, \binom{n}{2}, \binom{n}{3}$ form an arithmetic progression with $n > 3$ , then $n$ equals

$\textbf{(A)}\ 5\qquad \textbf{(B)}\ 7\qquad \textbf{(C)}\ 9\qquad \textbf{(D)}\ 11\qquad \textbf{(E)}\ 12$

Solution

Problem 9

A vertical line divides the triangle with vertices $(0,0), (1,1)$ , and $(9,1)$ in the $xy\text{-plane}$ into two regions of equal area. The equation of the line is $x=$

$\textbf {(A)}\ 2.5 \qquad \textbf {(B)}\ 3.0 \qquad \textbf {(C)}\ 3.5 \qquad \textbf {(D)}\ 4.0\qquad \textbf {(E)}\ 4.5$

Solution

Problem 10

In the adjoining diagram, $BO$ bisects $\angle CBA$ , $CO$ bisects $\angle ACB$ , and $MN$ is parallel to $BC$ . If $AB=12, BC=24$ , and $AC=18$ , then the perimeter of $\triangle AMN$ is

$[asy] size(200); defaultpen(linewidth(0.7)+fontsize(10)); pair B=origin, C=(24,0), A=intersectionpoints(Circle(B,12), Circle(C,18))[0], O=incenter(A,B,C), M=intersectionpoint(A--B, O--O+40*dir(180)), N=intersectionpoint(A--C, O--O+40*dir(0)); draw(B--M--O--B--C--O--N--C^^N--A--M); label("$A$", A, dir(90)); label("$B$", B, dir(O--B)); label("$C$", C, dir(O--C)); label("$M$", M, dir(90)*dir(B--A)); label("$N$", N, dir(90)*dir(A--C)); label("$O$", O, dir(90));[/asy]$

$\textbf {(A)}\ 30 \qquad \textbf {(B)}\ 33 \qquad \textbf {(C)}\ 36 \qquad \textbf {(D)}\ 39 \qquad \textbf {(E)}\ 42$

Solution

Problem 11

How many integers with four different digits are there between $1,000$ and $9,999$ such that the absolute value of the difference between the first digit and the last digit is $2$ ?

$\textbf {(A)}\ 672 \qquad \textbf {(B)}\ 784 \qquad \textbf {(C)}\ 840 \qquad \textbf {(D)}\ 896 \qquad \textbf {(E)}\ 1008$

Solution

Problem 12

Let $f(x) = ax^7+bx^3+cx-5$ , where $a,b$ and $c$ are constants. If $f(-7) = 7$ , the $f(7)$ equals

$\textbf {(A)}\ -17 \qquad \textbf {(B)}\ -7 \qquad \textbf {(C)}\ 14 \qquad \textbf {(D)}\ 21\qquad \textbf {(E)}\ \text{not uniquely determined}$

Solution

Problem 13

If $a>1, b>1$ , and $p=\frac{\log_b(\log_ba)}{\log_ba}$ , then $a^p$ equals

$\textbf {(A)}\ 1 \qquad \textbf {(B)}\ b \qquad \textbf {(C)}\ \log_ab \qquad \textbf {(D)}\ \log_ba \qquad \textbf {(E)}\ a^{\log_ba}$

Solution

Problem 14

In the adjoining figure, points $B$ and $C$ lie on line segment $AD$ , and $AB, BC$ , and $CD$ are diameters of circle $O, N$ , and $P$ , respectively. Circles $O, N$ , and $P$ all have radius $15$ and the line $AG$ is tangent to circle $P$ at $G$ . If $AG$ intersects circle $N$ at points $E$ and $F$ , then chord $EF$ has length

$[asy] size(250); defaultpen(fontsize(10)); pair A=origin, O=(1,0), B=(2,0), N=(3,0), C=(4,0), P=(5,0), D=(6,0), G=tangent(A,P,1,2), E=intersectionpoints(A--G, Circle(N,1))[0], F=intersectionpoints(A--G, Circle(N,1))[1]; draw(Circle(O,1)^^Circle(N,1)^^Circle(P,1)^^G--A--D, linewidth(0.7)); dot(A^^B^^C^^D^^E^^F^^G^^O^^N^^P); label("$A$", A, W); label("$B$", B, SE); label("$C$", C, NE); label("$D$", D, dir(0)); label("$P$", P, S); label("$N$", N, S); label("$O$", O, S); label("$E$", E, dir(120)); label("$F$", F, NE); label("$G$", G, dir(100));[/asy]$

$\textbf {(A)}\ 20 \qquad \textbf {(B)}\ 15\sqrt{2} \qquad \textbf {(C)}\ 24 \qquad \textbf {(D)}\ 25 \qquad \textbf {(E)}\ \text{none of these}$

Solution

Problem 15

Let $[z]$ denote the greatest integer not exceeding $z$ . Let $x$ and $y$ satisfy the simultaneous equations

$\begin{align*} y&=2[x]+3 \\ y&=3[x-2]+5. \end{align*}$

If $x$ is not an integer, then $x+y$ is

$\textbf{(A) } \ \text{ an integer} \qquad \textbf{(B) } \ \text{ between 4 and 5} \qquad \textbf{(C) } \ \text{ between -4 and 4}\qquad\\ \textbf{(D) } \ \text{ between 15 and 16}\qquad \textbf{(E) } \ 16.5$

Solution

Problem 16

A wooden cube has edges of length $3$ meters. Square holes, of side one meter, centered in each face are cut through to the opposite face. The edges of the holes are parallel to the edges of the cube. The entire surface area including the inside, in square meters, is

$\textbf {(A)} \ 54 \qquad \textbf {(B)} \ 72 \qquad \textbf {(C)} \ 76 \qquad \textbf {(D)} \ 84\qquad \textbf {(E)} \ 86$

Solution

Problem 17

How many real numbers $x$ satisfy the equation $3^{2x+2}-3^{x+3}-3^{x}+3=0$ ?

$\textbf {(A)}\ 0 \qquad \textbf {(B)}\ 1 \qquad \textbf {(C)}\ 2 \qquad \textbf {(D)}\ 3 \qquad \textbf {(E)}\ 4$

Solution

Problem 18

In the adjoining figure of a rectangular solid, $\angle DHG=45^\circ$ and $\angle FHB=60^\circ$ . Find the cosine of $\angle BHD$ .

$[asy] import three;defaultpen(linewidth(0.7)+fontsize(10)); currentprojection=orthographic(1/3+1/10,1-1/10,1/3); real r=sqrt(3); triple A=(0,0,r), B=(0,r,r), C=(1,r,r), D=(1,0,r), E=O, F=(0,r,0), G=(1,0,0), H=(1,r,0); draw(D--G--H--D--A--B--C--D--B--F--H--B^^C--H); draw(A--E^^G--E^^F--E, linetype("4 4")); label("$A$", A, N); label("$B$", B, dir(0)); label("$C$", C, N); label("$D$", D, W); label("$E$", E, NW); label("$F$", F, S); label("$G$", G, W); label("$H$", H, S); triple H45=(1,r-0.15,0.1), H60=(1-0.05, r, 0.07); label("$45^\circ$", H45, dir(125), fontsize(8)); label("$60^\circ$", H60, dir(25), fontsize(8));[/asy]$

$\textbf{(A)}\ \frac{\sqrt{3}}{6} \qquad \textbf{(B)}\ \frac{\sqrt{2}}{6} \qquad \textbf{(C)}\ \frac{\sqrt{6}}{3} \qquad \textbf{(D)}\ \frac{\sqrt{6}}{4}\qquad \textbf{(E)}\ \frac{\sqrt{6}-\sqrt{2}}{4}$

Solution

Problem 19

Let $f(x)=|x-2|+|x-4|-|2x-6|$ for $2 \leq x\leq 8$ . The sum of the largest and smallest values of $f(x)$ is

$\textbf {(A)}\ 1 \qquad \textbf {(B)}\ 2 \qquad \textbf {(C)}\ 4 \qquad \textbf {(D)}\ 6 \qquad \textbf {(E)}\ \text{none of these}$

Solution

Problem 20

The number of pairs of positive integers $(x,y)$ which satisfy the equation $x^2+y^2=x^3$ is

$\textbf {(A)}\ 0 \qquad \textbf {(B)}\ 1 \qquad \textbf {(C)}\ 2 \qquad \textbf {(D)}\ \text{not finite} \qquad \textbf {(E)}\ \text{none of these}$

Solution

Problem 21

In the adjoining figure, the triangle $ABC$ is a right triangle with $\angle BCA=90^\circ$ . Median $CM$ is perpendicular to median $BN$ , and side $BC=s$ . The length of $BN$ is

$[asy] size(200); defaultpen(linewidth(0.7)+fontsize(10));real r=54.72; pair B=origin, C=dir(r), A=intersectionpoint(B--(9,0), C--C+4*dir(r-90)), M=midpoint(B--A), N=midpoint(A--C), P=intersectionpoint(B--N, C--M); draw(M--C--A--B--C^^B--N); pair point=P; markscalefactor=0.01; draw(rightanglemark(B,C,N)); draw(rightanglemark(C,P,B)); label("$A$", A, dir(point--A)); label("$B$", B, dir(point--B)); label("$C$", C, dir(point--C)); label("$M$", M, S); label("$N$", N, dir(C--A)*dir(90)); label("$s$", B--C, NW); [/asy]$

$\textbf{(A)}\ s\sqrt 2 \qquad \textbf{(B)}\ \frac 32s\sqrt2 \qquad \textbf{(C)}\ 2s\sqrt2 \qquad \textbf{(D)}\ \frac{s\sqrt5}{2}\qquad \textbf{(E)}\ \frac{s\sqrt6}{2}$

Solution

Problem 22

In a narrow alley of width $w$ a ladder of length $a$ is placed with its foot at point $P$ between the walls. Resting against one wall at $Q$ , the distance $k$ above the ground makes a $45^\circ$ angle with the ground. Resting against the other wall at $R$ , a distance $h$ above the ground, the ladder makes a $75^\circ$ angle with the ground. The width $w$ is equal to

$\textbf{(A)}\ a\qquad \textbf{(B)}\ RQ\qquad \textbf{(C)}\ k\qquad \textbf{(D)}\ \frac{h+k}{2}\qquad \textbf{(E)}\ h$

Solution

Problem 23

The lengths of the sides of a triangle are consecutive integers, and the largest angle is twice the smallest angle. The cosine of the smallest angle is

$\textbf{(A)}\ \frac{3}{4}\qquad \textbf{(B)}\ \frac{7}{10}\qquad \textbf{(C)}\ \frac{2}{3}\qquad \textbf{(D)}\ \frac{9}{14}\qquad \textbf{(E)}\ \text{none of these}$

Solution

Problem 24

In the adjoining figure, the circle meets the sides of an equilateral triangle at six points. If $AG=2, GF=13, FC=1$ , and $HJ=7$ , then $DE$ equals

$[asy] defaultpen(fontsize(10)); real r=sqrt(22); pair B=origin, A=16*dir(60), C=(16,0), D=(10-r,0), E=(10+r,0), F=C+1*dir(120), G=C+14*dir(120), H=13*dir(60), J=6*dir(60), O=circumcenter(G,H,J); dot(A^^B^^C^^D^^E^^F^^G^^H^^J); draw(Circle(O, abs(O-D))^^A--B--C--cycle, linewidth(0.7)); label("$A$", A, N); label("$B$", B, dir(210)); label("$C$", C, dir(330)); label("$D$", D, SW); label("$E$", E, SE); label("$F$", F, dir(170)); label("$G$", G, dir(250)); label("$H$", H, SE); label("$J$", J, dir(0)); label("2", A--G, dir(30)); label("13", F--G, dir(180+30)); label("1", F--C, dir(30)); label("7", H--J, dir(-30));[/asy]$

$\textbf {(A)}\ 2\sqrt{22} \qquad \textbf {(B)}\ 7\sqrt{3} \qquad \textbf {(C)}\ 9 \qquad \textbf {(D)}\ 10 \qquad \textbf {(E)}\ 13$

Solution

Problem 25

The adjacent map is part of a city: the small rectangles are blocks, and the paths in between are streets. Each morning, a student walks from intersection $A$ to intersection $B$ , always walking along streets shown, and always going east or south. For variety, at each intersection where he has a choice, he chooses with probability $\frac{1}{2}$ whether to go east or south. Find the probability that through any given morning, he goes through $C$ .

$[asy] defaultpen(linewidth(0.7)+fontsize(8)); size(250); path p=origin--(5,0)--(5,3)--(0,3)--cycle; path q=(5,19)--(6,19)--(6,20)--(5,20)--cycle; int i,j; for(i=0; i<5; i=i+1) { for(j=0; j<6; j=j+1) { draw(shift(6*i, 4*j)*p); }} clip((4,2)--(25,2)--(25,21)--(4,21)--cycle); fill(q^^shift(18,-16)*q^^shift(18,-12)*q, black); label("A", (6,19), SE); label("B", (23,4), NW); label("C", (23,8), NW); draw((26,11.5)--(30,11.5), Arrows(5)); draw((28,9.5)--(28,13.5), Arrows(5)); label("N", (28,13.5), N); label("W", (26,11.5), W); label("E", (30,11.5), E); label("S", (28,9.5), S);[/asy]$

$\textbf{(A)}\ \frac{11}{32}\qquad \textbf{(B)}\ \frac{1}{2}\qquad \textbf{(C)}\ \frac{4}{7}\qquad \textbf{(D)}\ \frac{21}{32}\qquad \textbf{(E)}\ \frac{3}{4}$

Solution

Problem 26

If the base $8$ representation of a perfect square is $ab3c$ , where $a\ne 0$ , then $c$ equals

$\textbf{(A)}\ 0\qquad \textbf{(B)}\ 1 \qquad \textbf{(C)}\ 3\qquad \textbf{(D)}\ 4\qquad \textbf{(E)}\ \text{not uniquely determined}$

Solution

Problem 27

Suppose $z=a+bi$ is a solution of the polynomial equation $c_4z^4+ic_3z^3+c_2z^2+ic_1z+c_0=0,$ where $c_0, c_1, c_2, c_3, a,$ and $b$ are real constants and $i^2=-1.$ Which of the following must also be a solution?

$\textbf{(A)}\ -a-bi\qquad \textbf{(B)}\ a-bi\qquad \textbf{(C)}\ -a+bi\qquad \textbf{(D)}\ b+ai \qquad \textbf{(E)}\ \text{none of these}$

Solution

Problem 28

A set of consecutive positive integers beginning with $1$ is written on a blackboard. One number is erased. The average (arithmetic mean) of the remaining numbers is $35\frac{7}{17}$ . What number was erased?

$\textbf{(A)}\ 6\qquad \textbf{(B)}\ 7 \qquad \textbf{(C)}\ 8 \qquad \textbf{(D)}\ 9\qquad \textbf{(E)}\ \text{cannot be determined}$

Solution

Problem 29

Let $x,y,$ and $z$ be three positive real numbers whose sum is $1.$ If no one of these numbers is more than twice any other, then the minimum possible value of the product $xyz$ is

$\textbf{(A)}\ \frac{1}{32}\qquad \textbf{(B)}\ \frac{1}{36}\qquad \textbf{(C)}\ \frac{4}{125}\qquad \textbf{(D)}\ \frac{1}{127}\qquad \textbf{(E)}\ \text{none of these}$

Solution

Problem 30

Find the units digit of the decimal expansion of $\left(15 + \sqrt{220}\right)^{19} + \left(15 + \sqrt{220}\right)^{82}.$

$\textbf{(A)}\ 0\qquad \textbf{(B)}\ 2\qquad \textbf{(C)}\ 5\qquad \textbf{(D)}\ 9\qquad \textbf{(E)}\ \text{none of these}$

Solution

1982 AHSME (Problems • Answer Key • Resources)
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Difference between revisions of "1982 AHSME Problems"

Latest revision as of 18:05, 11 September 2023

Contents

Problem 1

Problem 2

Problem 3

Problem 4

Problem 5

Problem 6

Problem 7

Problem 8

Problem 9

Problem 10

Problem 11

Problem 12

Problem 13

Problem 14

Problem 15

Problem 16

Problem 17

Problem 18

Problem 19

Problem 20

Problem 21

Problem 22

Problem 23

Problem 24

Problem 25

Problem 26

Problem 27

Problem 28

Problem 29

Problem 30

See also

@@ Line 1: / Line 1: @@
+{{AHSME Problems
+|year = 1982
+}}
 == Problem 1 ==
 When the polynomial <math>x^3-2</math> is divided by the polynomial <math>x^2-2</math>, the remainder is
-<math>\text{(A)} \ 2 \qquad
+<math>\textbf{(A)} \ 2 \qquad
-\text{(B)} \ -2 \qquad
+\textbf{(B)} \ -2 \qquad
-\text{(C)} \ -2x-2 \qquad
+\textbf{(C)} \ -2x-2 \qquad
-\text{(D)} \ 2x+2 \qquad
+\textbf{(D)} \ 2x+2 \qquad
-\text{(E)} \ 2x-2</math>
+\textbf{(E)} \ 2x-2</math>
 [[1982 AHSME Problems/Problem 1|Solution]]
@@ Line 15: / Line 18: @@
 If a number eight times as large as <math>x</math> is increased by two, then one fourth of the result equals
-<math>\text{(A)} \ 2x + \frac{1}{2} \qquad
+<math>\textbf{(A)} \ 2x + \frac{1}{2} \qquad
-\text{(B)} \ x + \frac{1}{2} \qquad
+\textbf{(B)} \ x + \frac{1}{2} \qquad
-\text{(C)} \ 2x+2 \qquad
+\textbf{(C)} \ 2x+2 \qquad
-\text{(D)}\ 4\qquad
+\textbf{(D)}\ 2x+4 \qquad
-\text{(E)}\ 8  </math>
+\textbf{(E)}\ 2x+16  </math>
 [[1982 AHSME Problems/Problem 2|Solution]]
@@ Line 27: / Line 30: @@
 Evaluate <math>(x^x)^{(x^x)}</math> at <math>x = 2</math>.
-<math>\text{(A)} \ 16 \qquad
+<math>\textbf{(A)} \ 16 \qquad
-\text{(B)} \ 64 \qquad
+\textbf{(B)} \ 64 \qquad
-\text{(C)} \ 256 \qquad
+\textbf{(C)} \ 256 \qquad
-\text{(D)} \ 1024 \qquad
+\textbf{(D)} \ 1024 \qquad
-\text{(E)} \ 65,536 </math>
+\textbf{(E)} \ 65,536 </math>
 [[1982 AHSME Problems/Problem 3|Solution]]
@@ Line 40: / Line 43: @@
 measured in square centimeters. The radius of the semicircle, measured in centimeters, is
-<math>\text{(A)} \pi \qquad
+<math>\textbf{(A)} \ \pi \qquad
-\text{(B)} \frac{2}{\pi} \qquad
+\textbf{(B)} \ \frac{2}{\pi} \qquad
-\text{(C)} 1 \qquad
+\textbf{(C)} \ 1 \qquad
-\text{(D)}\frac{1}{2}\qquad
+\textbf{(D)} \ \frac{1}{2}\qquad
-\text{(E)}\frac{4}{\pi}+2  </math>
+\textbf{(E)} \ \frac{4}{\pi}+2  </math>
 [[1982 AHSME Problems/Problem 4|Solution]]
@@ Line 54: / Line 55: @@
 Two positive numbers <math>x</math> and <math>y</math> are in the ratio <math>a: b</math> where <math>0 < a < b</math>. If <math>x+y = c</math>, then the smaller of <math>x</math> and <math>y</math> is
-<math>\text{(A)} \ \frac{ac}{b} \qquad
+<math>\textbf{(A)} \ \frac{ac}{b} \qquad
-\text{(B)} \ \frac{bc-ac}{b} \qquad
+\textbf{(B)} \ \frac{bc-ac}{b} \qquad
-\text{(C)} \ \frac{ac}{a+b} \qquad
+\textbf{(C)} \ \frac{ac}{a+b} \qquad
-\text{(D)}\ \frac{bc}{a+b}\qquad
+\textbf{(D)}\ \frac{bc}{a+b}\qquad
-\text{(E)}\ \frac{ac}{b-a}  </math>
+\textbf{(E)}\ \frac{ac}{b-a}  </math>
 [[1982 AHSME Problems/Problem 5|Solution]]
@@ Line 66: / Line 67: @@
 The sum of all but one of the interior angles of a convex polygon equals <math>2570^\circ</math>. The remaining angle is
-<math>\text{(A)} \ 90^\circ \qquad
+<math>\textbf{(A)} \ 90^\circ \qquad
-\text{(B)} \ 105^\circ \qquad
+\textbf{(B)} \ 105^\circ \qquad
-\text{(C)} \ 120^\circ \qquad
+\textbf{(C)} \ 120^\circ \qquad
-\text{(D)}\ 130^\circ\qquad
+\textbf{(D)}\ 130^\circ\qquad
-\text{(E)}\ 144^\circ </math>
+\textbf{(E)}\ 144^\circ </math>
 [[1982 AHSME Problems/Problem 6|Solution]]
@@ Line 78: / Line 79: @@
 If the operation <math>x \star y</math> is defined by <math>x \star y = (x+1)(y+1) - 1</math>, then which one of the following is FALSE?
-<math>\text{(A)} \ x \star y = y\star x  \text{ for all real } x,y. \\
+<math>\textbf{(A)} \ x \star y = y\star x  \text{ for all real } x,y. \\
-\text{(B)} \ x \star (y + z) = ( x \star y ) + (x \star z)  \text{ for all real } x,y, \text{ and } z.\\
+\textbf{(B)} \ x \star (y + z) = ( x \star y ) + (x \star z)  \text{ for all real } x,y, \text{ and } z.\\
-\text{(C)} \ (x-1) \star (x+1) = (x \star x) - 1 \text{ for all real } x. \\
+\textbf{(C)} \ (x-1) \star (x+1) = (x \star x) - 1 \text{ for all real } x. \\
-\text{(D)} \ x \star 0 = x \text{ for all real } x. \\
+\textbf{(D)} \ x \star 0 = x \text{ for all real } x. \\
-\text{(E)} \ x \star (y \star z) = (x \star y) \star z \text{ for all real } x,y, \text{ and } z.   </math>
+\textbf{(E)} \ x \star (y \star z) = (x \star y) \star z \text{ for all real } x,y, \text{ and } z.   </math>
 [[1982 AHSME Problems/Problem 7|Solution]]
@@ Line 98: / Line 99: @@
 [[1982 AHSME Problems/Problem 8|Solution]]
 == Problem 9 ==
@@ Line 104: / Line 105: @@
 The equation of the line is <math>x=</math>
-<math>\text {(A)} 2.5 \qquad
+<math>\textbf {(A)}\ 2.5 \qquad
-\text {(B)} 3.0 \qquad
+\textbf {(B)}\ 3.0 \qquad
-\text {(C)} 3.5 \qquad
+\textbf {(C)}\ 3.5 \qquad
-\text {(D)} 4.0\qquad
+\textbf {(D)}\ 4.0\qquad
-\text {(E)} 4.5   </math>
+\textbf {(E)}\ 4.5   </math>
 [[1982 AHSME Problems/Problem 9|Solution]]
@@ Line 129: / Line 130: @@
 label("$O$", O, dir(90));</asy>
-<math>\text {(A)} 30 \qquad
+<math>\textbf {(A)}\ 30 \qquad
-\text {(B)} 33 \qquad
+\textbf {(B)}\ 33 \qquad
-\text {(C)} 36 \qquad
+\textbf {(C)}\ 36 \qquad
-\text {(D)} 39 \qquad
+\textbf {(D)}\ 39 \qquad
-\text {(E)} 42   </math>
+\textbf {(E)}\ 42   </math>
 [[1982 AHSME Problems/Problem 10|Solution]]
@@ Line 142: / Line 143: @@
 the difference between the first digit and the last digit is <math>2</math>?
-<math>\text {(A)} 672 \qquad
+<math>\textbf {(A)}\ 672 \qquad
-\text {(B)} 784 \qquad
+\textbf {(B)}\ 784 \qquad
-\text {(C)} 840 \qquad
+\textbf {(C)}\ 840 \qquad
-\text {(D)} 896 \qquad
+\textbf {(D)}\ 896 \qquad
-\text {(E)} 1008</math>
+\textbf {(E)}\ 1008</math>
 [[1982 AHSME Problems/Problem 11|Solution]]
@@ Line 154: / Line 155: @@
 Let <math>f(x) = ax^7+bx^3+cx-5</math>, where <math>a,b</math> and <math>c</math> are constants. If <math>f(-7) = 7</math>, the <math>f(7)</math> equals
-<math>\text {(A)} -17 \qquad
+<math>\textbf {(A)}\ -17 \qquad
-\text {(B)} -7 \qquad
+\textbf {(B)}\ -7 \qquad
-\text {(C)} 14 \qquad
+\textbf {(C)}\ 14 \qquad
-\text {(D)} 21\qquad
+\textbf {(D)}\ 21\qquad
-\text {(E)} \text{not uniquely determined}</math>
+\textbf {(E)}\ \text{not uniquely determined}</math>
 [[1982 AHSME Problems/Problem 12|Solution]]
@@ Line 166: / Line 167: @@
 If <math>a>1, b>1</math>, and <math>p=\frac{\log_b(\log_ba)}{\log_ba}</math>, then <math>a^p</math> equals
-<math>\text {(A)} 1 \qquad
+<math>\textbf {(A)}\ 1 \qquad
-\text {(B)} b \qquad
+\textbf {(B)}\ b \qquad
-\text {(C)} \log_ab \qquad
+\textbf {(C)}\ \log_ab \qquad
-\text {(D)} \log_ba \qquad
+\textbf {(D)}\ \log_ba \qquad
-\text {(E)} a^{\log_ba} </math>
+\textbf {(E)}\ a^{\log_ba} </math>
 [[1982 AHSME Problems/Problem 13|Solution]]
@@ Line 197: / Line 198: @@
 label("$G$", G, dir(100));</asy>
-<math>\text {(A)} 20 \qquad
+<math>\textbf {(A)}\ 20 \qquad
-\text {(B)} 15\sqrt{2} \qquad
+\textbf {(B)}\ 15\sqrt{2} \qquad
-\text {(C)} 24 \qquad
+\textbf {(C)}\ 24 \qquad
-\text{(D)} 25 \qquad
+\textbf {(D)}\ 25 \qquad
-\text {(E)} \text{none of these}</math>
+\textbf {(E)}\ \text{none of these}</math>
 [[1982 AHSME Problems/Problem 14|Solution]]
 == Problem 15 ==
@@ Line 213: / Line 214: @@
 If <math>x</math> is not an integer, then <math>x+y</math> is
-<math>\text {(A) } \text{ an integer} \qquad
+<math>\textbf{(A) } \ \text{ an integer} \qquad
-\text {(B) } \text{ between 4 and 5} \qquad
+\textbf{(B) } \ \text{ between 4 and 5} \qquad
-\text{(C) }\text{ between  -4 and 4}\qquad\\
+\textbf{(C) } \ \text{ between  -4 and 4}\qquad\\
-\text{(D) }\text{ between 15 and 16}\qquad
+\textbf{(D) } \ \text{ between 15 and 16}\qquad
-\text{(E) } 16.5  </math>
+\textbf{(E) } \  16.5  </math>
 [[1982 AHSME Problems/Problem 15|Solution]]
@@ Line 226: / Line 227: @@
 The edges of the holes are parallel to the edges of the cube. The entire surface area including the inside, in square meters, is
-<math>\text {(A)} 54 \qquad
+<math>\textbf {(A)} \ 54 \qquad
-\text {(B)} 72 \qquad
+\textbf {(B)} \ 72 \qquad
-\text {(C)} 76 \qquad
+\textbf {(C)} \ 76 \qquad
-\text {(D)} 84\qquad
+\textbf {(D)} \ 84\qquad
-\text {(E)} 86  </math>
+\textbf {(E)} \ 86  </math>
 [[1982 AHSME Problems/Problem 16|Solution]]
@@ Line 238: / Line 239: @@
 How many real numbers <math>x</math> satisfy the equation <math>3^{2x+2}-3^{x+3}-3^{x}+3=0</math>?
-<math>\text {(A)} 0 \qquad
+<math>\textbf {(A)}\ 0 \qquad
-\text {(B)} 1 \qquad
+\textbf {(B)}\ 1 \qquad
-\text {(C)} 2 \qquad
+\textbf {(C)}\ 2 \qquad
-\text {(D)} 3 \qquad
+\textbf {(D)}\ 3 \qquad
-\text {(E)} 4  </math>
+\textbf {(E)}\ 4  </math>
 [[1982 AHSME Problems/Problem 17|Solution]]
@@ Line 269: / Line 270: @@
 label("$60^\circ$", H60, dir(25), fontsize(8));</asy>
-<math>\text {(A)} \frac{\sqrt{3}}{6} \qquad
+<math>\textbf{(A)}\ \frac{\sqrt{3}}{6} \qquad
-\text {(B)} \frac{\sqrt{2}}{6} \qquad
+\textbf{(B)}\ \frac{\sqrt{2}}{6} \qquad
-\text {(C)} \frac{\sqrt{6}}{3} \qquad
+\textbf{(C)}\ \frac{\sqrt{6}}{3} \qquad
-\text{(D)}\frac{\sqrt{6}}{4}\qquad
+\textbf{(D)}\ \frac{\sqrt{6}}{4}\qquad
-\text{(E)}\frac{\sqrt{6}-\sqrt{2}}{4} </math>
+\textbf{(E)}\ \frac{\sqrt{6}-\sqrt{2}}{4} </math>
 [[1982 AHSME Problems/Problem 18|Solution]]
@@ Line 281: / Line 282: @@
 Let <math>f(x)=|x-2|+|x-4|-|2x-6|</math> for <math>2 \leq x\leq 8</math>. The sum of the largest and smallest values of <math>f(x)</math> is
-<math>\text {(A)} 1 \qquad
+<math>\textbf {(A)}\ 1 \qquad
-\text {(B)} 2 \qquad
+\textbf {(B)}\ 2 \qquad
-\text {(C)} 4 \qquad
+\textbf {(C)}\ 4 \qquad
-\text {(D)} 6 \qquad
+\textbf {(D)}\ 6 \qquad
-\text {(E)}\text{none of these} </math>
+\textbf {(E)}\ \text{none of these} </math>
 [[1982 AHSME Problems/Problem 19|Solution]]
 == Problem 20 ==
 The number of pairs of positive integers <math>(x,y)</math> which satisfy the equation <math>x^2+y^2=x^3</math> is
-<math>\text {(A)} 0 \qquad
+<math>\textbf {(A)}\ 0 \qquad
-\text {(B)} 1 \qquad
+\textbf {(B)}\ 1 \qquad
-\text {(C)} 2 \qquad
+\textbf {(C)}\ 2 \qquad
-\text {(D)} \text{not finite} \qquad
+\textbf {(D)}\ \text{not finite} \qquad
-\text {(E)} \text{none of these} </math>
+\textbf {(E)}\ \text{none of these} </math>
 [[1982 AHSME Problems/Problem 20|Solution]]
@@ Line 311: / Line 312: @@
 draw(M--C--A--B--C^^B--N);
 pair point=P;
-markscalefactor=0.005;
+markscalefactor=0.01;
+draw(rightanglemark(B,C,N));
 draw(rightanglemark(C,P,B));
 label("$A$", A, dir(point--A));
@@ Line 318: / Line 320: @@
 label("$M$", M, S);
 label("$N$", N, dir(C--A)*dir(90));
-label("$s$", B--C, NW);</asy>
+label("$s$", B--C, NW);
+</asy>
-<math>\text {(A)} s\sqrt 2 \qquad
+<math>\textbf{(A)}\ s\sqrt 2 \qquad
-\text {(B)} \frac 32s\sqrt2 \qquad
+\textbf{(B)}\ \frac 32s\sqrt2 \qquad
-\text {(C)} 2s\sqrt2 \qquad
+\textbf{(C)}\ 2s\sqrt2 \qquad
-\text{(D)}\frac{1}{2}s\sqrt5\qquad
+\textbf{(D)}\ \frac{s\sqrt5}{2}\qquad
-\text{(E)}\frac{1}{2}s\sqrt6</math>
+\textbf{(E)}\ \frac{s\sqrt6}{2}</math>
 [[1982 AHSME Problems/Problem 21|Solution]]
 == Problem 22 ==
-In a narrow alley of width <math>w</math> a ladder of length a is placed with its foot at point P between the walls.
+In a narrow alley of width <math>w</math> a ladder of length <math>a</math> is placed with its foot at point <math>P</math> between the walls.
-Resting against one wall at <math>Q</math>, the distance k above the ground makes a <math>45^\circ</math> angle with the ground.
+Resting against one wall at <math>Q</math>, the distance <math>k</math> above the ground makes a <math>45^\circ</math> angle with the ground.
-Resting against the other wall at <math>R</math>, a distance h above the ground, the ladder makes a <math>75^\circ</math> angle with the ground.
+Resting against the other wall at <math>R</math>, a distance <math>h</math> above the ground, the ladder makes a <math>75^\circ</math> angle with the ground. The width <math>w</math> is equal to
-The width <math>w</math> is equal to
-<math> \text{(A)}a\qquad
+<math> \textbf{(A)}\ a\qquad
-\text{(B)}RQ\qquad
+\textbf{(B)}\ RQ\qquad
-\text{(C)}k\qquad
+\textbf{(C)}\ k\qquad
-\text{(D)}\frac{h+k}{2}\qquad
+\textbf{(D)}\ \frac{h+k}{2}\qquad
-\text{(E)}h </math>
+\textbf{(E)}\ h </math>
 [[1982 AHSME Problems/Problem 22|Solution]]
 == Problem 23 ==
@@ Line 348: / Line 350: @@
 The cosine of the smallest angle is
-<math> \text{(A)}\frac{3}{4}\qquad
+<math> \textbf{(A)}\ \frac{3}{4}\qquad
-\text{(B)}\frac{7}{10}\qquad
+\textbf{(B)}\ \frac{7}{10}\qquad
-\text{(C)}\frac{2}{3}\qquad
+\textbf{(C)}\ \frac{2}{3}\qquad
-\text{(D)}\frac{9}{14}\qquad
+\textbf{(D)}\ \frac{9}{14}\qquad
-\text{(E)}\text{none of these} </math>
+\textbf{(E)}\ \text{none of these} </math>
 [[1982 AHSME Problems/Problem 23|Solution]]
 == Problem 24 ==
@@ Line 381: / Line 383: @@
 label("7", H--J, dir(-30));</asy>
-<math>\text {(A)} 2\sqrt{22} \qquad
+<math>\textbf {(A)}\ 2\sqrt{22} \qquad
-\text {(B)} 7\sqrt{3} \qquad
+\textbf {(B)}\ 7\sqrt{3} \qquad
-\text {(C)} 9 \qquad
+\textbf {(C)}\ 9 \qquad
-\text {(D)} 10 \qquad
+\textbf {(D)}\ 10 \qquad
-\text {(E)} 13</math>
+\textbf {(E)}\ 13</math>
 [[1982 AHSME Problems/Problem 24|Solution]]
@@ Line 391: / Line 393: @@
 == Problem 25 ==
-The adjacent map is part of a city: the small rectangles are rocks, and the paths in between are streets.
+The adjacent map is part of a city: the small rectangles are blocks, and the paths in between are streets.
 Each morning, a student walks from intersection <math>A</math> to intersection <math>B</math>, always walking along streets shown,
 and always going east or south. For variety, at each intersection where he has a choice, he chooses with
@@ Line 418: / Line 420: @@
 label("S", (28,9.5), S);</asy>
-<math> \text{(A)}\frac{11}{32}\qquad
+<math> \textbf{(A)}\ \frac{11}{32}\qquad
-\text{(B)}\frac{1}{2}\qquad
+\textbf{(B)}\ \frac{1}{2}\qquad
-\text{(C)}\frac{4}{7}\qquad
+\textbf{(C)}\ \frac{4}{7}\qquad
-\text{(D)}\frac{21}{32}\qquad
+\textbf{(D)}\ \frac{21}{32}\qquad
-\text{(E)}\frac{3}{4} </math>
+\textbf{(E)}\ \frac{3}{4} </math>
+[[1982 AHSME Problems/Problem 25|Solution]]
-[[1982 AHSME Problems/Problem 26|Solution]]
 == Problem 26 ==
 If the base <math>8</math> representation of a perfect square is <math>ab3c</math>, where <math>a\ne 0</math>, then <math>c</math> equals
-<math>\text{(A)} 0\qquad
+<math>\textbf{(A)}\ 0\qquad
-\text{(B)}1 \qquad
+\textbf{(B)}\ 1 \qquad
-\text{(C)} 3\qquad
+\textbf{(C)}\ 3\qquad
-\text{(D)} 4\qquad
+\textbf{(D)}\ 4\qquad
-\text{(E)} \text{not uniquely determined} </math>
+\textbf{(E)}\ \text{not uniquely determined} </math>
 [[1982 AHSME Problems/Problem 26|Solution]]
@@ Line 440: / Line 442: @@
 == Problem 27 ==
-Suppose <math>z=a+bi</math> is a solution of the polynomial equation <math>c_4z^4+ic_3z^3+c_2z^2+ic_1z+c_0=0</math>, where <math>c_0, c_1, c_2, c_3, a</math>, and <math>b</math>
+Suppose <math>z=a+bi</math> is a solution of the polynomial equation <cmath>c_4z^4+ic_3z^3+c_2z^2+ic_1z+c_0=0,</cmath> where <math>c_0, c_1, c_2, c_3, a,</math> and <math>b</math> are real constants and <math>i^2=-1.</math> Which of the following must also be a solution?
-are real constants and <math>i^2=-1</math>. Which of the following must also be a solution?
-<math>\text{(A)} -a-bi\qquad
+<math>\textbf{(A)}\ -a-bi\qquad
-\text{(B)} a-bi\qquad
+\textbf{(B)}\ a-bi\qquad
-\text{(C)} -a+bi\qquad
+\textbf{(C)}\ -a+bi\qquad
-\text{(D)}b+ai \qquad
+\textbf{(D)}\ b+ai \qquad
-\text{(E)} \text{none of these} </math>
+\textbf{(E)}\ \text{none of these} </math>
 [[1982 AHSME Problems/Problem 27|Solution]]
 == Problem 28 ==
-A set of consecutive positive integers beginning with <math>1</math> is written on a blackboard.
+A set of consecutive positive integers beginning with <math>1</math> is written on a blackboard. One number is erased. The average (arithmetic mean) of the remaining numbers is <math>35\frac{7}{17}</math>. What number was erased?
-One number is erased. The average (arithmetic mean) of the remaining numbers is <math>35\frac{7}{17}</math>. What number was erased?
-<math>\text{(A)} 6\qquad
+<math>\textbf{(A)}\ 6\qquad
-\text{(B)}7 \qquad
+\textbf{(B)}\ 7 \qquad
-\text{(C)}8 \qquad
+\textbf{(C)}\ 8 \qquad
-\text{(D)} 9\qquad
+\textbf{(D)}\  9\qquad
-\text{(E)}\text{cannot be determined}   </math>
+\textbf{(E)}\ \text{cannot be determined}</math>
 [[1982 AHSME Problems/Problem 28|Solution]]
 == Problem 29 ==
-Let <math>x,y</math>, and <math>z</math> be three positive real numbers whose sum is <math>1</math>. If no one of these numbers is more than twice any other,
+Let <math>x,y,</math> and <math>z</math> be three positive real numbers whose sum is <math>1.</math> If no one of these numbers is more than twice any other,
 then the minimum possible value of the product <math>xyz</math> is
@@ Line 476: / Line 476: @@
 [[1982 AHSME Problems/Problem 29|Solution]]
 == Problem 30 ==
-Find the units digit of the decimal expansion of
+Find the units digit of the decimal expansion of <cmath>\left(15 + \sqrt{220}\right)^{19} + \left(15 + \sqrt{220}\right)^{82}.</cmath>
-<math>(15 + \sqrt{220})^{19} + (15 + \sqrt{220})^{82}</math>.
 <math>\textbf{(A)}\ 0\qquad