Sometimes when dividing, you end up with a bit extra. For example, if I try and divide 20 by 6, I can fit 6 into 20 exactly 3 times and get 18, however there is still a 2 left over. This is a remainder, the result left over from a division when number being divided isnt divisible by the number dividing (e.g 20 isn't divisible by 6, so there is a remainder). We say the remainder after the soltion, for example, with 20/6, we would say the solution as 3 remainder 2, or 3 R 2