Scientific American presents Math Dude by Quick & Dirty Tips. Scientific American and Quick & Dirty Tips are both Macmillan companies. Long time math fans may remember our first foray into the world ...

CALCULATING percentage isn't always the easiest thing to do, but is a useful aide for anyone, especially if they can do so off the top of their head. Express.co.uk has compiled a handy guide on how to ...

How to calculate percentages is easier than you think. Quick, what’s 36% of 25? Or how about 250% of 20? Learn a quick and dirty tip to help you calculate all of those pesky percentages in your head.

One way to find a percentage of an amount is to use 1%, 10% and 50% as building blocks. 1%, 10% and 50% can be used as building blocks for working out percentages in your head. 1% is 1⁄100. Work out 1 ...