Prime Factorization and Greatest Common Factor (GCF)
Prime Number:
Composite Number:
Factor:
Prime Factor:
Prime Factorization:
a) Making a factor tree.
Notes:
Greatest Common Factor:
(GCF)
b) Finding the GCF using factor lists:
c) Finding the GCF using prime factorization:
Example:
Homework
a) Circle the prime numbers:
12
5
8
51
16
57
63
9
17
26
3
39
b) Draw a factor tree for each of the following:
24
64
250
120
c) Write each as a product of prime factors (use exponents to make it simpler, if possible)
256 –
81 –
504 –
316 875 –
d) Find the GCF for each pair using factor lists:
20, 24
72,48
54,81
e) Find the GCF for each of the following sets using prime factorization (show your factor trees!!):
36, 48, 60
27, 63, 81