# How do you find the greatest common factor of 24, 28?

Dec 2, 2016

Find the prime factorization for both numbers and multiply all common factors.

#### Explanation:

You could find the prime factorizations of $24$ and $28$.

$24 = {2}^{2} \cdot 3$

$28 = {2}^{2} \cdot 7$

We see that $24$ and $28$ have ${2}^{2}$ in common and nothing else, so the greatest common factor is

${2}^{2} = 4$

There are other ways to find the GCF as well such as listing out all the factors of each number and picking out the greatest, which is a little more tedious and unnecessary.