The factors of 4 are 1, 2, and 4 because 4 divides by 1, 2, and 4
The factors of 6 are 1, 2, 3 and 6 because 6 divides by 1, 2, 3 and 6
The common factors of 4 and 6 are 1 and 2
since 1 and 2 are factors of both 4 and 6

 

The factors of 8 are 1, 2, 4, and 8 because 8 divides by 1, 2, 4, and 8
The factors of 24 are 1, 2, 3, 4, 6, 8, 12 and 24 because 24 divides by 1, 2, 3, 4, 6, 8, 12 and 24
The common factors of 8 and 24 are 1, 2, 4 and 8
since 1, 2, 4 and 8 are factors of both 8 and 24