Encyclopedia > Peasant multiplication

  Article Content

Peasant multiplication

Peasant multiplication is an old algorithm for multiplication. It requires no use of a multiplication table; however, it requires that the user be able to divide by 2. The user must also know how to add.

  • Write the two numbers (A and B) you wish to multiply, each at the head of a column.
  • Starting with A, divide by 2 until there is nothing left to divide. Write the series of results under A.
  • Starting with B, keep doubling until you have doubled it as many times as you divided the first number. Write the series of results under B.
  • Add up all the numbers in the B-column that are next to an odd number in the A-column. This gives you the result.

Example: 27 times 82

A-columnB-columnAdd this
278282
13164164
6328
3656656
113121312
Result: 2214



All Wikipedia text is available under the terms of the GNU Free Documentation License

 
  Search Encyclopedia

Search over one million articles, find something about almost anything!
 
 
  
  Featured Article
Kings Park, New York

... the town the population is spread out with 25.2% under the age of 18, 5.7% from 18 to 24, 31.9% from 25 to 44, 23.3% from 45 to 64, and 13.9% who are 65 years of age ...

 
 
 
This page was created in 25.4 ms