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Re: Russian Peasant Multiplication / was question on how to do this

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  • Subject: [mg131349] Re: Russian Peasant Multiplication / was question on how to do this
  • From: d.a.paxton at gmail.com
  • Date: Sun, 30 Jun 2013 03:29:22 -0400 (EDT)
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On Saturday, June 29, 2013 2:47:03 AM UTC-6, Richard Fateman wrote:
> Dave --
>
> 1.  You should try to come up with a useful subject line
>
> in the future.
>
> 2. It is called Russian Peasant Multiplication (which you may
>
> find on Google).
>
> 3. There is no reason to believe that a procedural algorithm
>
> has a formula, but in this case I think the inverse is known
>
> as division :)

I am sorry for posting a question that is improper.  It is a matter of rounding as a floor or ceiling question I guess wondering nomenclature.  If the lowest count on the numbers in a multiply are let's say 7 and 5.  We multiple these and get 35.  How does on drop the 5 into the lowest of the answer and carry the 3?  Since 7 and 5 and also 35 are know known we do this..  In base ten we multiply by ten.  Divide out the seven and get fifty.  Divide that by ten and get the 5 drop out number.  Then put the the thirty five minus the drop out number and then divide by ten again.  Gives three.  The carry number.  So I guess in using this for any base number system we do have a divide as an inverse function for any variables in the course of a multiply.



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