Question

A sphere has a radius of 9 feet. A second sphere has a radius of 6 feet. What is the difference of the volumes of the spheres?

Answer 1

Difference of the volumes of the spheres=volume greater sphere - volume smaller sphere.

Volume of a sphere=(4/3)πr³

Difference of the volumes of the spheres=(4/3)πr₁³ - (4/3)πr₂³=(4/3)π(r₁³-r₂³)

Data:
r₁=9 ft
r₂=6 ft

then :

Difference of the volumes of the spheres=4/3π[(9 ft)³ - (6 ft)³]=(4/3)π(513 ft³)=
≈2148.85 ft³.


Answer: 2148.85 ft³

Answer 2

Well the formula to find the volume of a sphere is 3/4(pi)r^3
sphere with the radius of 9: 3/4(pi)9^3 = 3053.63
sphere with the radius of 6: 3/4(pi)6^3 = 904.78
the difference: 2148.85