How to find GCF
Find the greatest common factor (GCF) of two numbers using prime factorization with step by step instructions. GCF is also called greatest common divisor (GCD) and highest common factor (HCF).
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Solutions to Math GCF problems
- 1 & 2
- 1 & 3
- 1 & 4
- 1 & 5
- 2 & 1
- 2 & 2
- 2 & 3
- 2 & 4
- 2 & 5
- 2 & 6
- 2 & 7
- 2 & 8
- 2 & 9
- 2 & 10
- 3 & 1
- 3 & 2
- 3 & 3
- 3 & 4
- 3 & 5
- 3 & 6
- 3 & 7
- 3 & 8
- 3 & 9
- 3 & 10
- 3 & 11
- 3 & 12
- 3 & 13
- 3 & 14
- 3 & 15
- 4 & 1
- 4 & 2
- 4 & 3
- 4 & 4
- 4 & 5
- 4 & 6
- 4 & 7
- 4 & 8
- 4 & 9
- 4 & 10
- 4 & 11
- 4 & 12
- 4 & 13
- 4 & 14
- 4 & 15
- 4 & 16
- 4 & 17
- 4 & 18
- 4 & 19
- 4 & 20
- 5 & 1
- 5 & 2
- 5 & 3
- 5 & 4
- 5 & 5
- 5 & 6
- 5 & 7
- 5 & 8
- 5 & 9
- 5 & 10
- 5 & 11
- 5 & 12
- 5 & 13
- 5 & 14
- 5 & 15
- 5 & 16
- 5 & 17
- 5 & 18
- 5 & 19
- 5 & 20
- 5 & 21
- 5 & 22
- 5 & 23
- 5 & 24
- 5 & 25
- 6 & 1
- 6 & 2
- 6 & 3
- 6 & 4
- 6 & 5
- 6 & 6
- 6 & 7
- 6 & 8
- 6 & 9
- 6 & 10
- 6 & 11
- 6 & 12
- 6 & 13
- 6 & 14
- 6 & 15
- 6 & 16
- 6 & 17
- 6 & 18
- 6 & 19
- 6 & 20
- 6 & 21
- 6 & 22
- 6 & 23
- 6 & 24
- 6 & 25
- 6 & 26
- 6 & 27
- 6 & 28
- 6 & 29
- 6 & 30
- 7 & 5
- 7 & 6
- 7 & 7
- 7 & 8
- 7 & 9
- 7 & 10
- 7 & 11
- 7 & 12
- 7 & 13
- 7 & 14
- 7 & 15
- 7 & 16
- 7 & 17
- 7 & 18
- 7 & 19
- 7 & 20
- 7 & 21
- 8 & 6
- 8 & 7
- 8 & 8
- 8 & 9
- 8 & 10
- 8 & 11
- 8 & 12
- 8 & 13
- 8 & 14
- 8 & 15
- 8 & 16
- 8 & 17
- 8 & 18
- 8 & 19
- 8 & 20
- 8 & 21
- 8 & 22
- 8 & 23
- 8 & 24
- 9 & 3
- 9 & 4
- 9 & 5
- 9 & 6
- 9 & 7
- 9 & 8
- 9 & 9
- 9 & 10
- 9 & 11
- 9 & 12
- 9 & 13
- 9 & 14
- 9 & 15
- 9 & 16
- 9 & 17
- 9 & 18
- 9 & 19
- 9 & 20
- 9 & 21
- 9 & 22
- 9 & 23
- 9 & 24
- 9 & 25
- 9 & 26
- 9 & 27
- 10 & 2
- 10 & 3
- 10 & 4
- 10 & 5
- 10 & 6
- 10 & 7
- 10 & 8
- 10 & 9
- 10 & 10
- 10 & 11
- 10 & 12
- 10 & 13
- 10 & 14
- 10 & 15
- 10 & 16
- 10 & 17
- 10 & 18
- 10 & 19
- 10 & 20
- 10 & 21
- 10 & 22
- 10 & 23
- 10 & 24
- 10 & 25
- 10 & 26
- 10 & 27
- 10 & 28
- 10 & 29
- 10 & 30
- 11 & 20
- 12 & 20
- 13 & 20
- 14 & 20
- 15 & 20
- 16 & 20
- 17 & 20
- 18 & 20
- 19 & 20
- 20 & 20
- 10 & 50
- 15 & 50
- 20 & 50
- 25 & 50
- 30 & 50
- 35 & 50
- 40 & 50
- 45 & 50