Question

Find the area of the largest side of a rectangular box whose volume is $135{cm}^3$ and whose two sides have lengths $3$ centimeters and $9$ centimeters.

• A. $27{cm}^2$
• B. $36{cm}^2$
• C. $39{cm}^2$
• D. $45{cm}^2$
• E. $48{cm}^2$

Answer 1

Answer: (D)

$45{cm}^2$

Volume of the rectangular box $=$length $\times$ width $\times$ height

$\Rightarrow 135=3\times 9\times h$

$\Rightarrow h=\frac{135}{27}=5$cm

So the two longest dimension of the box are $9$ and $5$.

$\therefore$ area of the largest side $=$ $9\times 5=45c{m}^2$