Question

Find the total surface area of a right circular cone with radius 6 cm and height 8 cm.

Answer 1

The formula of the total surface area of a cone with base radius ‘r’ and slant height ‘l’ is given as

Total Surface Area =

But we do not have the slant height. We are given that r = 6 cm and h = 8 cm. We find l using the relation

=

=

=

= 10.

Therefore, the slant height, l = 10 cm.

Substituting the values of r = 6 cm and l = 10 cm in the above equation and using in specified formula,

Total Surface Area =

=

=

Therefore the total surface area of the given cone is or 301.71 cm².