How to Find the Greatest Common Factor

Finding the Greatest Common Factor

The greatest common factor of two or more numbers can be found.

Imagine we wanted to find the greatest common factor of 12 and 18.

How to Find the Greatest Common Factor

Finding the greatest common factor is easy.

Question

What is the greatest common factor of the numbers 12 and 18?

Step-by-Step:

1

List the factors of 12.

Factors of 12 = 1, 2, 3, 4 ,6, 12

Don't forget: The factors of 12 are the numbers that divide exactly into 12, leaving no remainder.

2

List the factors of 18.

Factors of 18 = 1, 2, 3, 6, 9, 18

3

The largest factor that appears in both lists is the greatest common factor.

Factors of 12 = 1, 2, 3, 4, 6 , 12

Factors of 18 = 1, 3, 6 , 9, 18

Answer:

6 is the greatest common factor of 12 and 18.

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See Also

What is the greatest common factor What is a factor? Finding factors