Question

The height of the pyramid in the diagram is three times the radius of the cone. The base area of the pyramid is the same as the base area of the cone. What is the expression for the volume of the pyramid in terms of the radius rof the cone?

Answer 1

v = 3πr^2

• Explanation:

v=1/3bh

v=1/3(πr^2)h [because the bases are equal and the base of a cone is circle]

v=1/3(πr^2)(3r) [because the height is 3 times the radius]

v=π3r^2 [1/3 and 3 cancel and we times 3r and r^2]