Question

Given the volume of the metal-shape is $38808$ ${\text{cm}}^3$, find the surface area. $(\pi =22/7)$

Answer 1

$\frac{4}{3}\pi r^2=38808$
$\therefore r^3=38808\times \frac{3}{4}\times \frac{7}{22}$
=9261
$={\left(21\right)}^3$
or r=21cm
surface area $=4\pi r^2$
$=4\times \frac{22}{7}\times 21\times 21c{m}^2$
$=5544c{m}^2$