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#1 2010-12-28 05:23:07

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

Russian Multiplication

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. . (Or name it after your favorite ethnic group.)






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#2 2010-12-30 03:31:34

DrSteve
Member
Registered: 2010-11-15
Posts: 10

Re: Russian Multiplication

Very interesting. I believe that you should include the original numbers you're multiplying by in the table (in this example they are crossed out because 76 is even).

Without giving away the details to others that want to prove this, the solution involves powers of 2.


Challenge problem:This technique can be generalized  by using powers of n for any other fixed positive integer n>2. How would the algorithm change in this case? (Hint: you need one additional column).


If you're going to be taking the SAT, check out my book:
http://thesatmathprep.com/SAT_Sales_Page.html

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#3 2013-05-24 02:40:14

barbie19022002
Member
Registered: 2013-05-24
Posts: 1,314

Re: Russian Multiplication

For your kind information I searched this one in net it is actually Egyptian Multiplication.............


Jake is Alice's father, Jake is the ________ of Alice's father?
Why is T called island letter?
think, think, think and don't get up with a solution...

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#4 2013-05-24 03:01:46

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 84,730

Re: Russian Multiplication

Hi;

I am afraid that it is mostly referred to in books as Russian peasant multiplication.


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

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#5 2013-05-25 01:56:39

barbie19022002
Member
Registered: 2013-05-24
Posts: 1,314

Re: Russian Multiplication

Its very silly, why will the Russian peasants use multiplication..........


Jake is Alice's father, Jake is the ________ of Alice's father?
Why is T called island letter?
think, think, think and don't get up with a solution...

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#6 2013-05-25 04:45:38

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 84,730

Re: Russian Multiplication

If they did not multiply, they would be extinct.


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

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#7 2013-05-25 16:12:35

barbie19022002
Member
Registered: 2013-05-24
Posts: 1,314

Re: Russian Multiplication

Extinct? but peasants are still there in the world.... especially in India....


Jake is Alice's father, Jake is the ________ of Alice's father?
Why is T called island letter?
think, think, think and don't get up with a solution...

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#8 2013-05-25 21:16:05

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 84,730

Re: Russian Multiplication

That is true so they are multiplying.


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

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#9 2013-05-27 01:56:28

barbie19022002
Member
Registered: 2013-05-24
Posts: 1,314

Re: Russian Multiplication

But, why only multiplication...why not addition... though it is a long process..


Jake is Alice's father, Jake is the ________ of Alice's father?
Why is T called island letter?
think, think, think and don't get up with a solution...

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#10 2013-05-27 01:58:34

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 84,730

Re: Russian Multiplication

Hmmm, multiplying as in increasing the population.


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

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#11 2013-05-27 02:32:47

barbie19022002
Member
Registered: 2013-05-24
Posts: 1,314

Re: Russian Multiplication

but, if the population increases then all the natural resources will be over...


Jake is Alice's father, Jake is the ________ of Alice's father?
Why is T called island letter?
think, think, think and don't get up with a solution...

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#12 2013-05-27 02:43:03

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 84,730

Re: Russian Multiplication

That is true. But it is another question entirely.


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

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#13 2013-05-27 02:47:40

barbie19022002
Member
Registered: 2013-05-24
Posts: 1,314

Re: Russian Multiplication

Ya, but in any how it is getting connected to it..


Jake is Alice's father, Jake is the ________ of Alice's father?
Why is T called island letter?
think, think, think and don't get up with a solution...

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#14 2013-05-27 02:51:10

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 84,730

Re: Russian Multiplication

The comment was a play on words. Multiplying has two meanings.


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

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#15 2013-05-27 02:52:54

barbie19022002
Member
Registered: 2013-05-24
Posts: 1,314

Re: Russian Multiplication

Ya, I did understand that...


Jake is Alice's father, Jake is the ________ of Alice's father?
Why is T called island letter?
think, think, think and don't get up with a solution...

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#16 2013-05-27 02:56:23

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 84,730

Re: Russian Multiplication

Anyway, soroban is correct. If you can multiply and divide by 2 you can do RPM.


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

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#17 2013-05-28 02:39:24

barbie19022002
Member
Registered: 2013-05-24
Posts: 1,314

Re: Russian Multiplication

RPM- you mean russian peasant multiplication??


Jake is Alice's father, Jake is the ________ of Alice's father?
Why is T called island letter?
think, think, think and don't get up with a solution...

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#18 2013-05-28 05:06:02

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 84,730

Re: Russian Multiplication

It sure is. We already know those peasants know how to multiply.


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

Offline

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