Spheres:

The Area and Volume of the Sphere:

A = 4pr

Areas and Volumes of Similar Solids:

Theorem:
If a : b is the scale factor of two figures then:

1. The ratio of the corresponding perimeters is a : b.
2. The ratio of the lateral areas, base areas, and total areas is a²: b²
3. The ratio of volumes is a³: b³