If you divide 18 by 5 you get 3 with 3 left over .
What I mean is - 5 goes into 18 three times (3x5=15) and 3 is left over ie there are 3 numbers between 15 and 18.
Is this clear?
If not, I will give it a go again!
Well, 5 goes into 18 three times (5 x 3 = 15), with 3 over. That's the remainder - or you could break it down further into a decimal point, but since you asked what a remainder is, the answer's 3, REMAINDER 3.
Imagine you have a plate of eighteen cakes and you want to share them amongst yoursel and four others (that's five in total) how many will be left over?
They will get three each and there'll be three left over (the remainder.)
No doubt as soon as the others leave, you'll scoff the other three cakes...