The slant height of a right circular cone is 10 m and its height is 8 m. Find the area of its curved surface.

Question:
The slant height of a right circular cone is 10 m and its height is 8 m. Find the area of its curved surface.

[A].

30 m2

[B].

40 m2

[C].

60 m2

[D].

80 m2

Answer: Option C

Explanation:

l = 10 m,

h = 8 m.

So, r = l2 – h2 = (10)2 – 82 = 6 m.

Curved surface area = rl = ( x 6 x 10) m2 = 60 m2.