Question

Choose the correct answer in each of the following :

The volume of a right circular cone of height 24 cm is 1232 $c{m}^3$. Its curved surface area is

$\left(a\right)1254c{m}^2\left(b\right)704c{m}^2\left(c\right)550c{m}^2\left(d\right)462c{m}^2$

Answer 1

ANSWER:
(c) 550 $c{m}^2$
Let r cm be the radius of the cone.
The volume of the right circular cone = 1232 $c{m}^3$
Then we have:
$\frac{1}{3}\times \frac{22}{7}\times r^2\times 24=1232c{m}^3$

⇒$r^2=49$
⇒ r = 7 cm
Curved surface area of the cone =πrl
=$\frac{22}{7}\times 7\times (7^2+{24}^2)=550c{m}^2$