Example 1: Common Factors

Find the common factors of 30 and 20.

[1 mark]

Factors of 30:\,1,\,2,\,3,\,5,\,6,\,10,\,15,\,30

Factors of 20:\,1,\,2,\,4,\,5,\,10,\,20

Common factors of 30 and 20 are numbers that are found in both lists.

Common factors are 1,\,2,\,5,\,10