The slant height of a right circular cone is 10 m and its height is 8 m. Find the area of its curved surface. Answers:
A) 30 m2
B) 40 m2
C) 50 m2
D) 60 m2
E) 80 m2
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.   Answer: Option 60 m2
<result>D</result>
The slant height of a right circular cone is 10 m and its height is 8 m. Find the area of its curved surface.