1991 AJHSME Problems/Problem 21

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 (ProblemsAnswer KeyResources)
Preceded by
Problem 20
Followed by
Problem 22
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