Multiplying and dividing whole numbers by numbers greater than 0 and less than 1 can be broken into a whole number calculation followed by multiplying or dividing by a power of 10, for example 10, 100 ...

A maths tutor on TikTok has gone viral after he revealed a hack for quickly and easily multiplying by nine. Brady Kelly (@bradyyourtutor) from Orlando, Florida, opens the video boldly saying: ...

Also see: WATCH: Genius maths hacks: The 11 times table Our latest video (scroll up to see), multiplying teen numbers, was inspired by a hack sent in by one of our readers, Jack Greenblatt.

NARRATION:Back in the deepest, darkest depths of time, there lived a great mathemagician called Hypatia. Numbers fell under her spell one by one. With them, Hypatia could do anything. Now Hypatia is ...