# Greatest Common Factor (GCF) Worksheet (1 of 2)

------ Note: The Information above this point will not be sent to your printer --------

Fill in the missing numbers in the factor trees then write the prime factorization (the first one is done for you):

 6 1  ,  2  ,  3  ,  6 9 1  ,  3  ,  9 Common Factors 1  ,  3 Greatest Common Factor 3
 8 1  , 2  , 4  , 8 20 1  , 2  , 4  , 5  , 10  , 20 Common Factors 1  , 2  , 4 Greatest Common Factor 4
 16 1  , 2  , 4  , 8  ,  16  , 24 1  , 2  , 3  , 4  , 6  , 8  , 12  , 24 Common Factors 1  , 2  , 4 , 8 Greatest Common Factor 8
 12 1  , 2  , 3  , 4  ,  6  , 12 30 1  , 2  , 3  , 5  , 6  , 10  , 15  , 30 Common Factors 1  , 2  , 3 , 6 Greatest Common Factor 6
 36 1  , 2  , 3  , 4  , 6  , 9  , 12  , 18 , 36 54 1  , 2  , 3  , 6  , 9  , 18  , 27  , 54 Common Factors 1  , 2  , 3  , 6  , 9  , 18 Greatest Common Factor 18
 40 1  , 2  , 4  , 5  , 8  , 10  , 20  , 40 64 1  , 2  , 4  , 8  , 16  , 32  , 64 Common Factors 1  , 2  , 4  , 8 Greatest Common Factor 8

------ Note: The Information below this point will not be sent to your printer --------

A Printable Math Worksheet    -    By HelpingWithMath.com

## Related Resources

The various resources listed below are aligned to the same standard, (6NS04) taken from the CCSM (Common Core Standards For Mathematics) as the Factors and multiples Worksheet shown above.

Find the greatest common factor of two whole numbers less than or equal to 100 and the least common multiple of two whole numbers less than or equal to 12. Use the distributive property to express a sum of two whole numbers 1-100 with a common factor as a multiple of a sum of two whole numbers with no common factor. For example, express 36 + 8 as 4 (9 + 2). Apply and extend previous understandings of numbers to the system of rational numbers.

### Worksheet

Similar to the above listing, the resources below are aligned to related standards in the Common Core For Mathematics that together support the following learning outcome:

Compute fluently with multi-digit numbers and find common factors and multiples