# How do you find the greatest common factor of 14 42 91?

Dec 13, 2016

$7$ is greatest common factor.

#### Explanation:

First write each number as a product of prime numbers. Here we have $14$, $42$ and $91$ and their prime factors are

14=2×7

42=2×3×7

91=7×13

Now list all the common factors (if any prime is occurring more than one time in each number pick up as many times it is spearing in all the numbers).

In above case, however, we have just $7$, which repeats in all.

Hence, here $7$ is greatest common factor.