Count Use FingerMatics

This mathematical calculation just use finger as the tools, but because of our finger have limited number, so we just calculate in limited number. As our general knowledge that we just easily to calculate of multiplication below ten, we will have difficulties if multification of above number of 10. This calculation called as FingerMatics 

On my example is how easily to calculate using our finger the calculation number from 15 to 20, because of our limited finger number.

For example we count 16 x 17, if we use calculator we will get 272 with easily. We can also calcule this multiplication using our finger.

To calculate using hands
  • for number 16, folded your left 4 finger, because 20 - 16 = 4
  • for number 17, folded your right 3 finger, because 20 - 17 = 3
  • then multiply between your folded finger, 4 x 3 = 12
  • your open finger are 1 and 2 each finger multiply by 10, so equal with 10 and 20. This fingger is add become 10 + 20 = 30, then multiply by 2, 30 x 2 = 60.
  • The result of all calculation is add become, 12 + 60 = 72
  • The final calculation is add by 200, 72 + 200 = 272 is same with calculator.
For other calculation can be seen on the example excel picture on the below, you can see that this formula still valid even to calculate number more than 20, but our finger number is limited. \


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