Factors Prime Lesson
Prime Factors Step Down Method
Prime factors are the prime numbers that can be multiplied together to get any composite number.
eg., prime factors of 45 are 3 and 5
Start by dividing with the smallest prime number and work your way up, using all of the prime numbers up to and including that number, if needed.
How It Works
eg., 54
Start with the smallest prime number.
Can that number be divided by 2?
54 ÷ 2 = 27
Can that number be divided by 3?
27 ÷ 3 = 9
Can that number be divided by 3?
9 ÷ 3 = 3
Can that number be divided by 3?
3 ÷ 3 = 1
The prime numbers for 54 are 2 and 3.
Prime Factors Step Down Lesson
eg. What are the prime factors of 88?
(For each step, always start by dividing by the smallest prime number.)
- (divide 88 by 2)..................2 |88
- (divide 44 by 2)..................2 |44
- (divide 22 by 2)..................2 |22
- (divide 11 by 11)..............11 |11
- (divide 1 by 1)....................1 |1
The prime factors are 2 and 11.
The prime factors are the numbers on the left side.
Prime Factors Step Down Problem
eg. What are the prime factors of 48?
- (divide).................. |48
- (divide).................. |
- (divide).................. |
- (divide).................... |
- (divide).................... |
The prime factors are
Prime Factors Worksheets
Factors page
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