What is the greatest common factor of 32 and 28?

The GCF of 28 and 32 is 4.

The factors of 32 are 1, 2, 4, 8, 16, and 32.

The factors of 28 are 1, 2, 4, 7, 14, and 28.

The largest factor they have in common is 4, so it is the greatest common factor of 32 and 28.

Alternately, you can examine their prime factors.

The prime factors of 32 are 2, 2, 2, 2, and 2.

The prime factors of 28 are 2, 2, and 7.

The prime factors they have in common are 2 and 2, so the greatest common factor is 2 x 2 = 4.
It is 4