18/54 in simplest form

All we need to do is to divide both sides by the greatest number that those numbers can be divided by. In this case 18 will do the job for both:

18 : 18 = 1

54 : 18 = 3

So 18 : 54 in its lowest term is as much as 1 : 3

18 / 54 = 9 / 27 = 3 / 9 = 1 / 3