My daughter has to work out the highest common factor of 50 and 125. She has to do little diagrams breaking down the 50 and then 125. So we get - 50 = 2 x 5 squared and 125 = 5 cubed. The next stage is confusing us. According what she has been shown the HCF = 2 x 5 squared, but that equals 50 :/ Help?