Question

Which is greater, the volume of a hemisphere with
radius 2 cm or the total volume of two cones with
radius 2 cm and height 2 cm?

Answer 1

sphere is 4/3 pi r^3 hemisphere is 1/2 of a sphere.

cone is 1/3 area of the base * height.

SO

hemisphere is 1/2 * 4/3 * 3.14 * 2^3
is 16.746666 cm^3

cone is 1/3 (pi r^2) * height
1/3 * pi * 2^2 * 2
is 8.37 BUT you have to cones
so 2 * 8.37 = 16.746666

They are the same...