I know this is a silly question but I'm not that good with maths so really need help.
I want to add 20% to a number but it doesn't add up right.
for example 20% taken from 1000 is 800 but if i wanted to put 20% back on 800 i always come up with 960.
I just want to make it up to 1000 again. It's because i have different figures i have taken 20% off but need then back to the original.
Sorry for being so thick