Today’s math tip is how to quickly multiply by 4.

How to do it? Simply double the number, and then double that number again.

Example:
4 x 842 = 842 doubled is 1684, then that doubled again is 3368

Another One:
4 x 1123 = 1123 doubled is 2246, then that doubled again is 4492

And that’s all there is to it!