Russian Peasant Multiplication
Date: 08/19/97 at 14:40:52 From: S.Nickless Subject: Question for dr.Math I'm a pupil at Archbishop Ilsely Secondary School in England and have a maths project to do. The project is on "russian" or "peasant" multiplication. I have to investigate this and my research on the Web has hardly turned up anything. I really need some help so if you could give me any pointers and what are the appropriate formula and equations I would be really grateful. Thanks, Daniel Nickless
Date: 08/19/97 at 15:45:04 From: Doctor Sarah Subject: Re: Question for dr.Math Hi Daniel - Here's an explanation from the Explorer site. http://explorer.scrtec.org/explorer/explorer-db/html/806787711-81ED7D49.html The so-called "Russian Peasant Method of Multiplication" is based on the binary system. There are said to be places in Africa where this method is still used. To multiply 92 x 37, write 92 at the top of one column and 37 at the top of another. Divide 92 by 2 and multiply 37 by 2, writing the results below the original numbers. 92 x 37 *46 74 *23 148 148 *11 296 296 5 592 592 2 1184 1 2368 2368 ---- 3404 Continue to divide by 2 in the first column and to multiply by 2 in the second column. When an odd number is divided by 2, disregard the remainder. Stop when 1 is reached in the first column and all the numbers represented in the second column are opposite representations of odd numbers in the first column. The correct answer is 3404. After practicing with many problems, try to determine where this method of multiplication is related to the binary system. -Doctor Sarah, The Math Forum Check out our web site! http://mathforum.org/dr.math/
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