Multiplying in 9s using your fingers

Multiplying in 9s using your fingers

Postby Cecile » Sat Jul 31, 2010 7:37 am

This is how you can use your two hands when multiplying in 9s. Say, you have 3 x 9, you mark your third finger, then count the number of fingers at the left and at the right of your third finger. The fingers at the left of your third finger is 2 while the fingers at the right is 7, so you have 27.
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Postby donaldhall » Wed Nov 17, 2010 12:46 am

how about if its more than ten?

donaldhall
 

Re:

Postby Guest » Wed Dec 21, 2011 2:48 pm

donaldhall wrote:how about if its more than ten?

i have a better idea what about lets say 9x3 ... you multiply 3 with 10 and get 30 and minus 3 = 27 there you go
9x25 u get 250 and minus 25 = 225 there you go :D i made this up myself i dont think there is an equation like this :D
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