We all know how do addition on our fingers but I recently came across a system for doing a few mulitplications on your fingers as well.

Unfortunatley it only works for multipling the integers six through ten and is therefore more of an interesting bit of trivia than a practical thing.

Ok how it works.

You start by calling your thumbs 6s; then your index fingers 7s; your middle fingers 8s; your fourth fingers 9s and your little fingers 10s.

Then you take one of the numbers/fingers you want to muliply together and place their tips together. So if you wanted to work out 6*8 you would take the thumb from one hand and the middle finger from your other hand and put the two tips together making a bridge between your hands.

Then make sure your hands are orientated so that your thumbs are nearest to you and then count all the fingers before (close to you) and including the bridge made by your fingers. So in the exaple 6*8 you have the thumb on one hand and the first three fingers on the other hand making a total of four fingers. That number {4} is the first digit of the answer (the number of tens).

Then you look at the fingers on each hand on the far side of the bridge and multiply them together. So for 6*8 you get four fingers on one hand and two on the other so you get a total of 2*4 so 8. This number is the second digit of the solution.

So for 6*8 you get 48!

If you want to do 6*6 you get 2 for the fist digit and 16 for the second and you just have to combine the two sensibly, so 36 not 216! The same problem arises for 6*7, it's 42 not 312 and for 10*10 you have to carry the 1 so you get 100 not 10.

I have called this wu Mulitplying on your fingers but I have also heard it called "The Gypsy Method" and ariels tells me it is also called Russian Peasant Multiplication.

OK all you pedants out there I know you think a thumb isn't a finger but for this wu I have treated it as one in the interest of simplicity.

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