The volume of a rectangular box is $144 \mathrm{~cm}^{3}$. If its length is $12 \mathrm{~cm}$ and its width is $6 \mathrm{~cm}$, what is its height?
(A) $126 \mathrm{~cm}$
(B) $72 \mathrm{~cm}$
(C) $4 \mathrm{~cm}$
(D) $8 \mathrm{~cm}$
(E) $2 \mathrm{~cm}$
The volume of a rectangular box is $144 \mathrm{~cm}^{3}$. If its length is $12 \mathrm{~cm}$ and its width is $6 \mathrm{~cm}$, what is its height?
(A) $126 \mathrm{~cm}$
(B) $72 \mathrm{~cm}$
(C) $4 \mathrm{~cm}$
(D) $8 \mathrm{~cm}$
(E) $2 \mathrm{~cm}$

Solution

We know that Volume $=$ Length $¥$ Width $¥$ Height, the volume is $144 \mathrm{~cm}^{3}$, and

Length $¥$ Width $=72 \mathrm{~cm}^{2}$. Thus, $144 \mathrm{~cm}^{3}=72 \mathrm{~cm}^{2} ¥$ Height, or Height $=2 \mathrm{~cm}$.

ANSwer: (E)