Q12 of 79 Page 229

If the circumference of the base of a solid right circular cone is 236 cm and its slant height is 12 cm, find its curved surface area.

Given : Circumference of base of cone = 236 cm

Slant height of cone = l = 12 cm


To find : CSA of cone = ?


Formula : Circumference = 2r


CSA of cone = rl


Solution : Circumference = 2r


⇒ 2 × r = 236


r = = 118


CSA of cone = rl = 118 × 12 = 1416 cm2


∴ The curved surface area of the solid right circular cone is 1416 cm2.


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