Question

Approximately how many times as great is the volume of the grapefruit as the volume of the lime?
A. About 10 times as great.
B. About 4 times as great.
C. About 28 times as great.
D. About 8 times as great.

Answer 1

About four times as great

Answer 2

Volume of a hemisphere = 2/3πr^3
Volume of the grapefruit = 2/3π(5)^3 = 2/3π(125) = 250/3π
Volume of the lime = 2/3π(3)^3 = 2/3π(27) = 18π

Volume of grapefruit is 250/3π / 18π = 4.6 = about 4 times as great as the volume of the lime.