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Difference between revisions of "2009 AMC 10A Problems"

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(Problem 11)
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== Problem 11 ==
 
== Problem 11 ==
  
<math>
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One dimension of a cube is increased by <math>1</math>, another is decreased by <math>1</math>, and the third is left unchanged. The volume of the new rectangular solid is <math>5</math> less than that of the cube. What was the volume of the cube?
\mathrm{(A)}\  
+
 
\qquad
+
<math>\textbf{(A)}\ 8 \qquad \textbf{(B)}\ 27 \qquad \textbf{(C)}\ 64 \qquad \textbf{(D)}\ 125 \qquad \textbf{(E)}\ 216</math>
\mathrm{(B)}\  
 
\qquad
 
\mathrm{(C)}\  
 
\qquad
 
\mathrm{(D)}\  
 
\qquad
 
\mathrm{(E)}\  
 
</math>
 
  
 
[[2009 AMC 10A Problems/Problem 11|Solution]]
 
[[2009 AMC 10A Problems/Problem 11|Solution]]

Revision as of 04:07, 13 February 2009

Problem 1

One can holds $12$ ounces of soda. What is the minimum number of cans needed to provide a gallon (128 ounces) of soda?

$\mathrm{(A)}\ 7 \qquad \mathrm{(B)}\ 8 \qquad \mathrm{(C)}\ 9 \qquad \mathrm{(D)}\ 10 \qquad \mathrm{(E)}\ 11$

Solution

Problem 2

Four coins are picked out of a piggy bank that contains a collection of pennies, nickels, dimes and quarters. Which of the following could not be the total value of the four coins, in cents?

$\mathrm{(A)}\ 15 \qquad \mathrm{(B)}\ 25 \qquad \mathrm{(C)}\ 35 \qquad \mathrm{(D)}\ 45 \qquad \mathrm{(E)}\ 55$

Solution

Problem 3

Which of the following is equal to $1 + \frac{1}{1+\frac{1}{1+1}}$?

$\mathrm{(A)}\ \frac{5}{4} \qquad \mathrm{(B)}\ \frac{3}{2} \qquad \mathrm{(C)}\ \frac{5}{3} \qquad \mathrm{(D)}\ 2 \qquad \mathrm{(E)}\ 3$

Solution

Problem 4

Eric plans to compete in a triathalon. He can average $2$ miles per hour in the $\frac{1}{4}$-mile swim and $6$ miles per hour in the $3$-mile run. His goal is to finish the triathlon in $2$ hours. To accomplish his goal what must his average speed in miles per hour, be for the $15$-mile bicycle ride?

$\mathrm{(A)}\ \frac{120}{11} \qquad \mathrm{(B)}\ 11 \qquad \mathrm{(C)}\ \frac{56}{5} \qquad \mathrm{(D)}\ \frac{45}{4} \qquad \mathrm{(E)}\ 12$

Solution

Problem 5

What is the sum of the digits of the square of $111,111,111$?

$\mathrm{(A)}\ 18 \qquad \mathrm{(B)}\ 27 \qquad \mathrm{(C)}\ 45 \qquad \mathrm{(D)}\ 63 \qquad \mathrm{(E)}\ 81$

Solution

Problem 6

Solution

$\mathrm{(A)}\  \qquad \mathrm{(B)}\  \qquad \mathrm{(C)}\  \qquad \mathrm{(D)}\  \qquad \mathrm{(E)}$

Problem 7

A carton contains milk that is $2$% fat, an amount that is $40$% less fat than the amount contained in a carton of whole milk. What is the percentage of fat in whole milk?

$\mathrm{(A)}\ \frac{12}{5} \qquad \mathrm{(B)}\ \frac{10}{3} \qquad \mathrm{(C)}\ 9 \qquad \mathrm{(D)}\ 38 \qquad \mathrm{(E)}\ 42$

Solution

Problem 8

Three Generations of the Wen family are going to the movies, two from each generation. The two members of the youngest generation receive a $50$% discount as children. The two members of the oldest generation receive a $25\%$ discount as senior citizens. The two members of the middle generation receive no discount. Grandfather Wen, whose senior ticket costs <dollar/>$6.00$, is paying for everyone. How many dollars must he pay?

$\mathrm{(A)}\ 34 \qquad \mathrm{(B)}\ 36 \qquad \mathrm{(C)}\ 42 \qquad \mathrm{(D)}\ 46 \qquad \mathrm{(E)}\ 48$

Solution

Problem 9

Positive integers $a$, $b$, and $2009$, with $a<b<2009$, form a geometric sequence with an integer ratio. What is $a$?

$\mathrm{(A)}\ 7 \qquad \mathrm{(B)}\ 41 \qquad \mathrm{(C)}\ 49 \qquad \mathrm{(D)}\ 289 \qquad \mathrm{(E)}\ 2009$

Solution

Problem 10

$\mathrm{(A)}\  \qquad \mathrm{(B)}\  \qquad \mathrm{(C)}\  \qquad \mathrm{(D)}\  \qquad \mathrm{(E)}$

Solution

Problem 11

One dimension of a cube is increased by $1$, another is decreased by $1$, and the third is left unchanged. The volume of the new rectangular solid is $5$ less than that of the cube. What was the volume of the cube?

$\textbf{(A)}\ 8 \qquad \textbf{(B)}\ 27 \qquad \textbf{(C)}\ 64 \qquad \textbf{(D)}\ 125 \qquad \textbf{(E)}\ 216$

Solution

Problem 12

$\mathrm{(A)}\  \qquad \mathrm{(B)}\  \qquad \mathrm{(C)}\  \qquad \mathrm{(D)}\  \qquad \mathrm{(E)}$

Solution

Problem 13

$\mathrm{(A)}\  \qquad \mathrm{(B)}\  \qquad \mathrm{(C)}\  \qquad \mathrm{(D)}\  \qquad \mathrm{(E)}$

Solution

Problem 14

$\mathrm{(A)}\  \qquad \mathrm{(B)}\  \qquad \mathrm{(C)}\  \qquad \mathrm{(D)}\  \qquad \mathrm{(E)}$

Solution

Problem 15

$\mathrm{(A)}\  \qquad \mathrm{(B)}\  \qquad \mathrm{(C)}\  \qquad \mathrm{(D)}\  \qquad \mathrm{(E)}$

Solution

Problem 16

$\mathrm{(A)}\  \qquad \mathrm{(B)}\  \qquad \mathrm{(C)}\  \qquad \mathrm{(D)}\  \qquad \mathrm{(E)}$

Solution

Problem 17

$\mathrm{(A)}\  \qquad \mathrm{(B)}\  \qquad \mathrm{(C)}\  \qquad \mathrm{(D)}\  \qquad \mathrm{(E)}$

Solution

Problem 18

$\mathrm{(A)}\  \qquad \mathrm{(B)}\  \qquad \mathrm{(C)}\  \qquad \mathrm{(D)}\  \qquad \mathrm{(E)}$

Solution

Problem 19

$\mathrm{(A)}\  \qquad \mathrm{(B)}\  \qquad \mathrm{(C)}\  \qquad \mathrm{(D)}\  \qquad \mathrm{(E)}$

Solution

Problem 20

$\mathrm{(A)}\  \qquad \mathrm{(B)}\  \qquad \mathrm{(C)}\  \qquad \mathrm{(D)}\  \qquad \mathrm{(E)}$

Solution

Problem 21

$\mathrm{(A)}\  \qquad \mathrm{(B)}\  \qquad \mathrm{(C)}\  \qquad \mathrm{(D)}\  \qquad \mathrm{(E)}$

Solution

Problem 22

$\mathrm{(A)}\  \qquad \mathrm{(B)}\  \qquad \mathrm{(C)}\  \qquad \mathrm{(D)}\  \qquad \mathrm{(E)}$

Solution

Problem 23

$\mathrm{(A)}\  \qquad \mathrm{(B)}\  \qquad \mathrm{(C)}\  \qquad \mathrm{(D)}\  \qquad \mathrm{(E)}$

Solution

Problem 24

$\mathrm{(A)}\  \qquad \mathrm{(B)}\  \qquad \mathrm{(C)}\  \qquad \mathrm{(D)}\  \qquad \mathrm{(E)}$

Solution

Problem 25

$\mathrm{(A)}\  \qquad \mathrm{(B)}\  \qquad \mathrm{(C)}\  \qquad \mathrm{(D)}\  \qquad \mathrm{(E)}$

Solution