The diameter of the moon is approximately one fourth of the diameter of the earth. Find the ratio of their surface areas.

 Solution:

If diameter of earth is said d, then the diameter of moon will be d/4 (as per given statement)

Radius of earth = d/2

Radius of moon = ½×d/4 = d/8

Surface area of moon = 4π(d/8)2

Surface area of earth = 4π(d/2)2

The ratio between their surface areas is 1:16.