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#1 2009-06-28 07:52:35

soroban
Member
Registered: 2007-03-09
Posts: 451

Peasant Multiplication

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#2 2009-06-28 10:14:27

JaneFairfax
Member
Registered: 2007-02-23
Posts: 6,868

Re: Peasant Multiplication

Yep, I think I know why this works. You simply convert the number to be halved into base 2, which is a sum of powers of 2. When you multiply by the other number, it’s equivalent to multiplying each term in the sum by the other number and adding up.

In your example …


Q: Who wrote the novels Mrs Dalloway and To the Lighthouse?

A: Click here for answer.

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#3 2009-06-28 11:54:34

soroban
Member
Registered: 2007-03-09
Posts: 451

Re: Peasant Multiplication

Yes, you got it, Jane!
And a very nice explanation, too . . .

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#4 2009-07-17 00:33:12

nirzhor
Member
Registered: 2009-07-17
Posts: 1

Re: Peasant Multiplication

really this is cool.i have collected some cool technique to multiply but i want to know more.my collection is not a huge one but i want to make it huge so please help me sending cool math trick to me  (nirzhorahmad@gmail.com)
you can watch my collection at http://funmath123.blogspot.com/
visit the site and throw your comment

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