1. Finding GCF (Greatest Common Factor)
Lesson 4-3

2. Math Vocabulary
GCF (Greatest Common Factor): The highest number that can divide INTO two or more given numbers

3. Finding GCF
When finding GCF… finding the highest #, the given number(s) can be divided by… (Helpful hint: usually = the smallest given # or smaller)

4. Finding GCF Find the GCF of 40 and 60 can GCF = 40
must be less than 40
GCF = 20

5. Finding GCF Find the GCF of 6a³b and 4a²b GCF of #s Common variable(s)
Lowest exponent of each variable
GCF = 2a²b

6. Finding GCF Find the GCF of 12r³s⁵t² and 8r²s⁴t⁸ GCF of #s
Common variable(s)
Lowest exponent of each variable
GCF = 4r²s⁴t²

7. Practice
Find the GCF
8, 20
12a, 15bc
15m²n, 45m
14fg³h⁹, 35f ⁵h⁴

8. Homework
p #11-15, 29-44, 58-61