Answer: 384π inches
Explanation:
the formula for surface area of a cone = 2πrh
Circumference = 2πr
24π = 2πr
r = 24π/2π
r = 12
the radius of the base = 12inches
Using pythagoras theorem,
20^2 - 12^2 = 400 - 144 = 256 = 16^2
The height of the cone = 16inches
Therefore, the surface area of the cone= 2πrh
= 2 × π × 12× 16
=384π inches