What is the greatest common factor of 38 and 28?

Answer 1

First of all both numbers are expressed as the product of primes.

Prime factorization of 28 = 2 x 2 x 7

Prime factorization of 38 = 2 x 19

As it can be seen only 2 is common in prime factorization of both numbers.

2 is the only number except 1 that goes into 28 and 38. So, GCF(28, 38) = 2.

Answer 2

Factors of 38: 1, 2, 19, 38

Factors of 28: 1, 2, 4, 7, 14, 28

GCF (38, 28) = 2

Answer 3

The GCF of 28 and 38 is 2.