Question

Find the GCD:

(6) 42, 28, 70

Answer 1

The divisors of 42 are 1, 2, 3, 6, 7, 14, 21 and 42.
The divisors of 28 are 1, 2, 4, 7, 14 and 28.
The divisors of 70 are 1, 2, 5, 7, 10, 14, 35 and 70.
The common divisors are 1, 2, 7 and 14.
Thus, the GCD or HCF is 14.