Multiplication of 99 with any number

Pure mathematics is the world's best game. It is more absorbing than chess, more of a gamble than poker, and lasts longer than Monopoly. It's free. It can be played anywhere - Archimedes did it in a bathtub.

It is a mathematical fact that the casting of this pebble from my hand alters the centre of gravity of the universe.

M4Math helped me a lot.

Thanks m4 maths for helping to get placed in several companies.
I must recommend this website for placement preparations.