Finding the Greatest Common Factor

Think Backwards… Find Factors Circle Common Factors Group Greatest Factor

Step 1: Find the Factors 24 – 1,2,3,4,6,8,12,24 36 – 1,2,3,4,6,9,12,18,36

Step 2: Circle Common Factors 24 – 1,2,3,4,6,8,12,24 36 – 1,2,3,4,6,9,12,18,36

Step 3: Group the Greatest Factor 24 – 1,2,3,4,6,8,12,24 36 – 1,2,3,4,6,9,12,18,36

The Greatest Common Factor of 24 and 36 is… 12

Now let’s try finding the GCF

Find the GCF of 12 and 24 Step 1: Find the factors 12 – 1,2,3,4,6,12 24 – 1,2,3,4,6,8,12,24

Find the GCF of 12 and 24 Step 2: Circle the common factors 12 – 1,2,3,4,6,12 24 – 1,2,3,4,6,8,12,24

Find the GCF of 12 and 24 Step 3: Group the greatest factor 12 – 1,2,3,4,6,12 24 – 1,2,3,4,6,8,12,24

The Greatest Common Factor of 12 and 24 is …

Your turn! Find the Greatest Common Factor of 16 and 20. Remember…Find Factors, Circle Common, Group Greatest!

The Greatest Common Factor of 16 and 20 is… 4

Are you ready? Let's try some more!

On Your Own Page 203- 204 #1, 4, 9 Math Choice Board