Question

If the areas of circular bases of a frustum of a cone are 4 cm² and 9 cm² respectively and the height of the frustum is 12 cm. What is the volume of the frustum?

Answer 1

Area of circular bases of frustum is

`A_1 = 4 cm^2`

`A_2 = 4 cm^2`

The height of frustum h = 12 cm

Now, the volume of frustum

`V = h/3{A_1 + A_2 + sqrt(A_1 A_2)}`

   `=12/3 {4 + 9 + sqrt(4 xx 9)}`

   `=4 {13 + 6}`

`V = 76 cm^3`