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1991 AJHSME Problems/Problem 21

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Problem

For every 3^\circ rise in temperature, the volume of a certain gas expands by 4 cubic centimeters. If the volume of the gas is 24 cubic centimeters when the temperature is 32^\circ, what was the volume of the gas in cubic centimeters when the temperature was 20^\circ?

\text{(A)}\ 8 \qquad \text{(B)}\ 12 \qquad \text{(C)}\ 15 \qquad \text{(D)}\ 16 \qquad \text{(E)}\ 40

Solution

We know that T=32-3k\Rightarrow V=24-4k. Setting k=4, we get the volume when the temperature is 20^\circ, which is 24-4(4)=8\rightarrow \boxed{\text{A}}.

See Also

1991 AJHSME (ProblemsResources)
Preceded by
Problem 20
Followed by
Problem 22
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
Want to learn how to tackle those tough AMC/AIME/Olympiad counting and probability problems? Check out Art of Problem Solving's Intermediate Counting & Probability by David Patrick.
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