How is 4 the HCF of 28 and 60?

Answer 1

To figure out the HCF of 28 and 60, split them up into their prime factors:

28 = 2x2x7

60 = 2x2x3x5

The next step is to identify any common prime factors. In this case, both numbers have two 2s as prime factors. Multiply these together and you get:

2x2 = 4

Therefore 4 is the HCF of 28 and 60.