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#1 2010-12-29 04:23:07

soroban
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Russian Multiplication

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












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#2 2010-12-31 02:31:34

DrSteve
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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
 

#3 2013-05-25 00:40:14

barbie19022002
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Re: Russian Multiplication

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

 

#4 2013-05-25 01:01:46

bobbym
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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.
90% of mathematicians do not understand 90% of currently published mathematics.
I am willing to wager that over 75% of the new words that appeared were nothing more than spelling errors that caught on.
 

#5 2013-05-25 23:56:39

barbie19022002
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Re: Russian Multiplication

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

 

#6 2013-05-26 02:45:38

bobbym
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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.
90% of mathematicians do not understand 90% of currently published mathematics.
I am willing to wager that over 75% of the new words that appeared were nothing more than spelling errors that caught on.
 

#7 2013-05-26 14:12:35

barbie19022002
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Re: Russian Multiplication

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

 

#8 2013-05-26 19:16:05

bobbym
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Re: Russian Multiplication

That is true so they are multiplying.


In mathematics, you don't understand things. You just get used to them.
90% of mathematicians do not understand 90% of currently published mathematics.
I am willing to wager that over 75% of the new words that appeared were nothing more than spelling errors that caught on.
 

#9 2013-05-27 23:56:28

barbie19022002
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Re: Russian Multiplication

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

 

#10 2013-05-27 23:58:34

bobbym
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Re: Russian Multiplication

Hmmm, multiplying as in increasing the population.


In mathematics, you don't understand things. You just get used to them.
90% of mathematicians do not understand 90% of currently published mathematics.
I am willing to wager that over 75% of the new words that appeared were nothing more than spelling errors that caught on.
 

#11 2013-05-28 00:32:47

barbie19022002
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Re: Russian Multiplication

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

 

#12 2013-05-28 00:43:03

bobbym
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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.
90% of mathematicians do not understand 90% of currently published mathematics.
I am willing to wager that over 75% of the new words that appeared were nothing more than spelling errors that caught on.
 

#13 2013-05-28 00:47:40

barbie19022002
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Re: Russian Multiplication

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

 

#14 2013-05-28 00:51:10

bobbym
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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.
90% of mathematicians do not understand 90% of currently published mathematics.
I am willing to wager that over 75% of the new words that appeared were nothing more than spelling errors that caught on.
 

#15 2013-05-28 00:52:54

barbie19022002
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Re: Russian Multiplication

Ya, I did understand that...

 

#16 2013-05-28 00:56:23

bobbym
Administrator

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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.
90% of mathematicians do not understand 90% of currently published mathematics.
I am willing to wager that over 75% of the new words that appeared were nothing more than spelling errors that caught on.
 

#17 2013-05-29 00:39:24

barbie19022002
Power Member

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Re: Russian Multiplication

RPM- you mean russian peasant multiplication??

 

#18 2013-05-29 03:06:02

bobbym
Administrator

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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.
90% of mathematicians do not understand 90% of currently published mathematics.
I am willing to wager that over 75% of the new words that appeared were nothing more than spelling errors that caught on.
 

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