Question

The curved surface area of a cone is 4070 cm² and its diameter is 70 cm. What is its slant height? (Use $\mathrm{\pi }$ = 22/7).

Answer 1

It is given that the curved surface area (C.S.A) of the cone is 4070 cm² and that the base diameter is 70 cm. The formula of the curved surface area of a cone with base radius ‘r’ and slant height ‘l’ is given as

Curved Surface Area =

Hence, slant height, l =

The base radius is half of the base diameter. And since the base diameter is given as 70 cm we can find out the base radius as, r = 35 cm.

Substituting the values of C.S.A and the base radius and using in the above equation,

Slant height, l =

=

= 37

Hence the slant height of the cone with the mentioned dimensions is.