21 , 35 , 42

Find the common factors for the numerical part:

21,35,42

The factors for 21 are all numbers between 1 and 21, which divide 21 evenly.

Check numbers between 1 and 21

Find the factor pairs of 21 where x⋅y=21.

xy12137

List the factors for 21.

1,3,7,21

1,3,7,21

The factors for 35 are all numbers between 1 and 35, which divide 35 evenly.

Check numbers between 1 and 35

Find the factor pairs of 35 where x⋅y=35.

xy13557

List the factors for 35.

1,5,7,35

1,5,7,35

The factors for 42 are all numbers between 1 and 42, which divide 42 evenly.

Check numbers between 1 and 42

Find the factor pairs of 42 where x⋅y=42.

xy14222131467

List the factors for 42.

1,2,3,6,7,14,21,42

1,2,3,6,7,14,21,42

List all the factors for 21,35,42 to find the common factors.

21: 1,3,7,21

35: 1,5,7,35

42: 1,2,3,6,7,14,21,42

The common factors for 21,35,42 are 1,7.

1,7

The GCF (HCF) of the numerical factors 1,7 is 7.

7

Find the GCF 21 , 35 , 42