Suppose planet A?'s diameter is approximately 2 times planet B?'s and both bodies are spheres. What is the ratio of their volumes?

Answer 1

V = (4/3)pi(r^3)

if A's diameter = 2 x B's diameter, its radius is also twice as large

V of A = (4/3)pi(2r)^3= (4/3)pi(8r^3)

A's volume is 8 times as large as B's volume