Multiplying by numbers less than 11 is easy. However, using the fact that 11 = 10 + 1, there is a way to multiply by 11 quickly, in less than 15 seconds.

Put down the last digit of the number on the right-most side of the answer, like the image shows.

Sweet!

I actually do know a bit about the method pictured on the right of the main picture, but why do you have that when you are explaining a totally different method?

or just multiply by 10 and add the number ( 4370 +437 in this case) :-) <br>