Problem #2105


A company sells peanut butter in cylindrical jars. Marketing research suggests that using wider jars would increase sales. If the diameter of the jars is increased by $25\%$ without altering the volume, by what percent must the height be decreased?

$\text {(A)} 10\% \qquad \text {(B)} 25\% \qquad \text {(C)} 36\% \qquad \text {(D)} 50\% \qquad \text {(E)}60\%$

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