Question

Which pair of numbers is relatively prime?

A) 15 and 21
B) 24 and 49
C) 35 and 135
D) 45 and 102

Answer 1

B

Explanation:

Two numbers are relatively prime when there is no integer greater than one that that is a factor of both of them.

A: 15 and 21 both have a factor of 3.

B: 24 and 49 have no common factors, and therefore, are relatively prime.

C. 35 and 135 both have a factor of 5.

D: 45 and 102 both have a factor of 3.