Multiply Up to 20X20 – (tricks)

In just FIVE minutes you should learn to quickly multiply up to 20x20 in your head. With this trick, you will be able to multiply any two numbers from 11 to 19 quickly, without the use of a calculator.

Try this:

Take 15 x 13 for an example.

Always place the larger number of the two on top in your mind.

Then draw the shape of Africa mentally so it covers the 15 and the 3 from the 13
below. Those covered numbers are all you need.

First add 15 + 3 = 18

Add a zero behind it (multiply by 10) to get 180.

Multiply the covered lower 3 x the single digit above it the "5" (3x5= 15)

Add 180 + 15 = 195.

Practice it on paper first