Question

The curved surface area of a cylindrical pillar is $264$ m${}^2$ and its volume is $924$ m${}^3$. Find the diameter.

Answer 1

$V=\pi r^{2}h$ & $CSA=2\pi rh$

$\Rightarrow \frac{V}{\left(CSA\right)}=\frac{\pi r^{2}h}{2\pi rh}=\frac{r}{2}\Rightarrow d=4\times \frac{924}{264}$

$\Rightarrow d=14$