# Greatest common factor worksheets

Being able to find the greatest common factor of a number is an important math skill. The greatest common factor worksheets in this page are applicable for grade 4 and up students. These worksheets includes method of finding the greatest common factor, and examples of how they are used. Examples are provided in each worksheet. So kids can get help with the given examples.

Prime factors
A prime factorization shows how to write a number as the product of prime factors.

Ex.Write the prime factorization of 10.
Divide by prime factors until the quotient is 1.
10÷2= 5
5÷5= 1
The prime factorization of 10 is: 2 × 5

How to find the GCF of numbers
The greatest common factor is the greatest whole number that is a factor of each of two or more numbers.
Ex.What is the greatest common factor of 20 and 4?
Write the prime factorization for each number.
20= 2 × 2 × 5
4= 2 × 2
Next, find the common factors shared by both of the numbers.
20= 2 × 2 × 5
4 = 2 × 2

Finally, multiply the common factors to find the greatest common factor.
2 × 2 = 4
The greatest common factor of 20 and 4 is 4.

How to Find the GCF of a Monomials
Compute the GCF of the coefficients of the monomials.It is the way that first factoring each of the coefficients. Then next for common factors within the factorization and multiply those factors together.

You will find here many GCF worksheets with basic, medium and hard levels.