1. Greatest Common Factor
FRACTIONS
Greatest Common Factor

2. Using What You Know . . . LEAST COMMON MULTIPLE GREATEST COMMON FACTOR
Helps find Common Denominators
GREATEST COMMON FACTOR
Helps Reduce fractions

3. GREATEST COMMON FACTOR
Using What You Learned . . .
GREATEST COMMON FACTOR
Helps reduce fractions
What’s the GCF??
What factors do they share?
Which of those factors is the largest?
= ?

4. GREATEST COMMON FACTOR
Using What You Learned . . .
GREATEST COMMON FACTOR
Helps reduce fractions
What’s the GCF??
You can list the factors
You can make factor trees
= ?

5. GREATEST COMMON FACTOR
Using What You Learned . . .
What’s the GCF??
Factor Tree
Circle the # when it is prime
Line up the factors 6:
9: GCF = 3
GREATEST COMMON FACTOR
Helps reduce fractions
= ?

6. Greatest Common Factor5 20
THINK . . .
Greatest The biggest possible
Common They both have it
Factor A factor of both numbers

7. Greatest Common Factor
HINT
The GCF will ALWAYS be
EQUAL to Or
SMALLER than
the smallest of the two
(or three numbers)

8. Greatest Common Factor
3 and 7
All of these numbers are PRIME.
IF both numbers are PRIME, the GCF will be 1.
5 and 7
11 and 13

9. Greatest Common Factor
All of these numbers are PRIME.
IF both numbers are PRIME, the GCF will be 1.
3 and 7 1 1
5 and 7
11 and 13 1

10. Give It A Try – What’s the GCF?
3 and 5
12 and 20
5, 3, and 7
3 and 9
4 and 12
6 and 12
10 and 25
14 and 24
6 and 9
15 and 100 6 1 4 5 1 2 3 3 5 4