Question

Which pair of numbers is relatively prime?

A.
18 and 45

B.
26 and 91

C.
10 and 33

D.
14 and 63

Answer 1

The answer is C)

The numbers are relatively prime if there is no common factor that divides both of them apart from 1.  A) isn't answer because 3 is one of common factors. B isn't answer because 13 is common factor. and D isn't answer because 7 is common factor.

Therefore only 10 and 31 have no common factors other than 1