Skills · The Number System · Factors & Multiples
Greatest common factor
Printable practice with an answer key the engine computes, at three levels, in as many versions as you need.
Problem types
- two numbers up to 30: GCF of 12 and 18
- one number divides the other: GCF of 8 and 24
- two numbers up to 100: GCF of 36 and 60
- nothing in common (GCF 1): GCF of 9 and 16
- three numbers: GCF of 12, 18 and 30
- past 100, through prime factorizations: GCF of 120 and 180
Sample Sheet · Level 1
- GCF of 6 and 30 =
- GCF of 8 and 24 =
- GCF of 7 and 21 =
- GCF of 8 and 12 =
- GCF of 6 and 21 =
- GCF of 9 and 27 =
- GCF of 15 and 20 =
- GCF of 10 and 22 =
Answer key
- 6
- 8
- 7
- 4
- 3
- 9
- 5
- 2
Sample Sheet · Level 3
- GCF of 24, 32 and 48 =
- GCF of 90 and 108 =
- GCF of 40 and 180 =
- GCF of 117 and 195 =
- GCF of 78 and 130 =
- GCF of 56, 60 and 36 =
- GCF of 54, 48 and 30 =
- GCF of 40, 20 and 50 =
Answer key
- 8
- 18
- 20
- 39
- 26
- 4
- 6
- 10
Make your own
Pick the count, the level and the version, and print it with work space and the key on its own page. The same skill also makes an I Do, We Do, You Do lesson, a Mosaic, a Decoder and more.