Question

Find the GCD:

(7) 60, 90

Answer 1

The divisors of 60 are 1, 2, 3, 4, 5, 6, 10, 12, 15, 20, 30 and 60.
The divisors of 90 are 1, 2, 3, 5, 6, 9, 10, 15, 18, 30, 45 and 90.
The common divisors are 1, 2, 3, 5, 6, 10, 15 and 30.
Thus, the GCD or HCF is 30.