# How do you find the greatest common factor of 30, 18, and 12?

Jan 5, 2017

You factorize each number into primes:

#### Explanation:

$30 = \textcolor{red}{2} \textcolor{w h i t e}{\times 2} \times \textcolor{red}{3} \textcolor{w h i t e}{\times 3} \times 5$

$18 = \textcolor{red}{2} \textcolor{w h i t e}{\times 2} \times \textcolor{red}{3} \times 3$

$12 = \textcolor{red}{2} \times 2 \times \textcolor{red}{3}$

What they all have in common is $2 \times 3 = 6$