6/25 - 4/5.......u should choose the lowest common denominator which is 25. 6/25 - 20/25 = - 14/25
however, even if u didn't pick the lowest....lets say u picked 50 6/25 - 4/5 = 12/50 - 40/50 = - 28/50 reduces to - 14/25...u will still get the same answer...u will just have to reduce
the reason u want to pick the lowest common denominator is because it is easier....if u dont pick the lowest, u will have to reduce....so picking the lowest just saves you time.
6/25 - 4/5.......u should choose the lowest common denominator which is 25. 6/25 - 20/25 = - 14/25
however, even if u didn't pick the lowest....lets say u picked 50 6/25 - 4/5 = 12/50 - 40/50 = - 28/50 reduces to - 14/25...u will still get the same answer...u will just have to reduce
the reason u want to pick the lowest common denominator is because it is easier....if u do not pick the lowest, u will have to reduce....so picking the lowest just saves you time. also u can round up or down if u wanna be more smart