Who wouldn't like to master math naturally, being able to do perform mental calculation without the help of a calculator?
If you had to calculate the square of 115 in a few seconds what would you answer? Or the product 238x5, or even the square of 76?
With this guide you will become masters of fast mental calculation, you will surprise your friends with your skills and you will be astonished when you discover that reaching apparently impossible goals can be achieved with very little effort.