What is the greatest common factor of 32 and 40?

The GCF of 32 and 40 is 8.

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

The factors of 40 are 1, 2, 4, 5, 8, 10, 20, and 40.

The common factors are 1, 2, 4, and 8, so the greatest common factor is 8.

You can also determine the greatest common factor from the prime factors.

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

The prime factors of 40 are 2, 2, 2, and 5.

The prime factors they have in common are 2, 2, and 2, so the greatest common factor is 2 x 2 x 2 = 8.
It is: 8
The GCF is 8.