Question

The area of the base of a right circular cylinder is $616c{m}^2$ and its height is 2.5 cm. Find the curved surface area of the cylinder.

Answer 1

Let r be the radius of the base of the cylinder, then
Area of the base = $\pi r^2$
$\therefore \pi r^2=616\Rightarrow \frac{22}{7}{r}^2=616\Rightarrow r^2=\frac{616\times 7}{22}=28\times 7=196=(14{)}^2$
$\therefore r=14cm$
Height (h) of the cylinder =2.5 cm
$\therefore Curvedsurfacearea=2\pi rh$
$=2\times \frac{22}{7}\times 14\times 2.5c{m}^2$
$=220.0c{m}^2=220c{m}^2$