Everyday math

> Egyptian Multiplication Method <

Egyptian Method

Multiplying two numbers that does not require the
multiplication table, only the ability to multiply and divide by
2, and to add.

Example : Multiply 83 * 27
The first column starts with a 1, and doubling is done until one reaches the
largest power of two not exceeding the first factor. The second column starts
with the second factor, and repeatedly doubles as often as was done in the
first column.

Working bottom to top identifies the subset of entries in the first column that
adds up to the first factor, and crosses out the other entries.

Add up the corresponding entries in the second column.

egyptian multiplication