1. 932840276498713209129318947 48209830958569408909284234 GREATESTCOMMONFACTOR

2. The Greatest Common Factor GCF of two or more numbers is the largest factor they have in common. METHOD 1 List all the factors of each number Find the largest common factor METHOD 2 Divide both numbers by the same factors – multiply all these factors There are two different methods for finding the GCF of a set of numbers. Let’s take a look at both ways!!!!!

3. The Greatest Common Factor GCF of two or more numbers is the largest factor they have in common. Find the GCF of 12 and 18 METHOD 1 List all the factors of each number Find the largest common factor Factors of 12 = 1, 2, 3, 4, 6, 12 Factors of 18 = 1, 2, 3, 6, 9, 18 Circle the greatest factor they have in common The Greatest Common Factor GCF is 6

4. The Greatest Common Factor GCF of two or more numbers is the largest factor they have in common. Find the GCF of 12 and 18 METHOD 2 Divide both numbers by the same factors – multiply all these factors The Greatest Common Factor GCF is 6 12 18 2 6 93 2 3 2 x 3 = 6 6 x 2 =12 6 x 3 = 18 CHECK:

5. Find the Greatest Common Factor GCF of 24 and 36 METHOD 1 ALL FACTORS METHOD 2 DIVISION 24 = 1, 2, 3, 4, 6, 8, 12, 24 36 = 1, 2, 3, 4, 6, 9, 12, 18, 36 Circle greatest common factor GCF = 12 24 364 6 93 2 3 Multiply common factors GCF = 4 x 3 = 12 12 x 2 = 24 12 x 3 = 36 CheckCheck

6. The Greatest Common Factor GCF of two or more numbers is the largest factor they have in common. Find the GCF of 90 and 120 METHOD 2 Repeated Division The Greatest Common Factor GCF is 30 90 120 10 9 123 3 4 10 x 3 = 30 30 x 3 = 90 30 x 4 = 120 CHECK:

7. The Greatest Common Factor GCF of two or more numbers is the largest factor they have in common. Find the GCF of 14 and 20 METHOD 2 Repeated Division The Greatest Common Factor GCF is 2 14 20 2 7 10 2 2 x 7 =14 2 x 10 = 20 CHECK:

8. The Greatest Common Factor GCF of two or more numbers is the largest factor they have in common. Find the GCF of 32 and 80 METHOD 2 Repeated Division The Greatest Common Factor GCF is 16 32 80 2 16 404 4 10 2 x 4 x 2 = 16 16 x 2 =32 16 x 5 = 80 2 5 2 CHECK:

9. The Greatest Common Factor GCF of two or more numbers is the largest factor they have in common. Find the GCF of 77 and 15 METHOD 2 Repeated Division The Greatest Common Factor GCF is 1 77 15 1 1 1 x 77 = 77 1 x 15 = 15 CHECK:

10. The Greatest Common Factor GCF of two or more numbers is the largest factor they have in common. Find the GCF of 36, 48, and 30 METHOD 2 Repeated Division The Greatest Common Factor GCF is 6 36 4830 2 18 24 15 3 6 8 5 2 x 3 = 6 6 x 6 =36 6 x 8 = 48 6 x 5 =30 CHECK:

11. **ASSIGNMENT** Page 236 (#8-17, 37-38)Page 236 (#8-17, 37-38) Do Your Best!