Question

The volume of a sphere is $38808{cm}^3$. Find its surface area.

Answer 1

Let radius of the sphere be r
Volume of sphere $=38808{cm}^3$
$\Rightarrow \frac{4}{3}\pi r^3=38808$
$\Rightarrow \frac{4}{3}\times \frac{22}{7}\times r^3=38808$
$r^3=\frac{38808\times 7\times 3}{4\times 22}$
$\begin{array}{cc}{r}^3& =9261\\ r^3& =21\times 21\times 21\\ r& ={\left[\right(21{)}^3]}^{1/3}\\ & =21cm\end{array}$
$\therefore$ Surface area of sphere $=4\pi r^2$
$\begin{array}{c}=4\times \frac{22}{7}\times (21{)}^2\\ =4\times \frac{22}{7}\times 21\times 21\\ =5544{cm}^2\end{array}$
Hence, the surface area of sphere $=5544{cm}^2$