Question

What is the Hcf of 25 and 125

Answer 1

25=5x5 -- the same as
`5^2`
125=5x5x5 -- the same as
`5^(3)`

As we can see there are 2 5s in the prime factors of 25 and 3 in the prime factors of 125. Therefore we pick the maximum number that is in both, which is 2, to get the HCF.


`5*5=25`

The HCF of 25 and 125 is 25.