Download Prime Factorization

Name
Chapter 1, Lesson 3
Reteach
Date
Prime Factorization
CA Standards
NS 1.4, MR 2.3
Jason needs to find all of the factors of 60 for his math homework. Follow the steps he
used to find the prime factorization of 60.
Step 1 Find two numbers
with a product of 60 (do not
use 1 and 60). Write them
as branches of a factor tree.
60
Step 2 Write each composite number as a product
of two factors. Circle prime
numbers. Continue until
the numbers at the ends of
branches are prime numbers.
Step 3 Write all the prime
number factors in order from
least to greatest.
60 = 2 × 2 × 3 × 5
60
6 × 10
6
×
10
2×3×2×5
Solution: The prime factorization of 60 is 2 × 2 × 3 × 5.
Complete each factor tree. Then write the prime factorization.
1.
2.
15
×3
3 ×
18
4.
5.
× 2
9
3×
×
9
3 ×
20
6.
54
9 × 2
3 ×
3.
21
6
× 2 ×3
5 × 4
5 ×
×
Writing Math Explain how making a factor tree can help you
find the prime factorization of a number.
Reteach
Use with text pages 12–13.
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