Question

Is 30 and 138 relatively prime

Answer 1

Is 30 and 138 relatively prime?

Answer: 30 and 138 are composite numbers but Both numbers have prime numbers. 

Factors of 138: 1, 2, 3, 6, 23, 46, 69, 138
Factors of 30: 1, 2, 3, 5, 6, 10, 15, 30     

They both have the same prime numbers, So your Answer to your Question is Yes, They are relatively prime! :) 

   Good luck and Have a nice Sweet Benevolent Day!

Answer 2

Yes, If the two numbers have no factors in common then they are relatively prime.