SSC CGL 16 Aug 2015 Shift 1 Paper

Let the radius of the base of conical tent be r metre and its height be h metre.
∴ Area of base = $\mathit{\pi }{\mathit{r}}^2$
= 16 × 5 = 80 ......(i)
Volume = $\frac{1}{3}\mathit{\pi }{\mathit{r}}^2\mathit{h}$
= 5 × 100 cu. metre ......(ii)
On dividing equation (ii) by (i),
$\frac{1}{3}\frac{\mathit{\pi }{\mathit{r}}^2\mathit{h}}{\mathit{\pi }{\mathit{r}}^2}$ = $\frac{5\times 100}{80}$
⇒$\frac{\mathit{h}}{3}$ = $\frac{25}{4}$
⇒ h = $\frac{75}{4}$ = 18.75 metre