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 EGYPTIAN ARITHMETIC Numbers and Operations

We have very few traces of Egyptian arithmetic from a date earlier than the original sources of the Rhind papyrus. But before this date there was a long period of Egyptian civilization, and we may well believe that for more than a thousand years there had been a slow development of the elaborate system before us.

The Egyptians apparently conceived of two kinds of numbers, an ascending series from 1 to 1,000,000 of numbers that we call integers, and a corresponding descending series consisting of ⅔ and reciprocal numbers or unit fractions.

For integers they had

1. A well-defined decimal notation, without, however, the positional device that renders our modern notation so simple;

2. A thorough understanding of the four arithmetical operations,—addition, subtraction, multiplication, and division.

Addition and subtraction were easily accomplished. Direct multiplication by integers was generally confined to the multipliers 2 and 10; that is, in cases where the process was explicit, and it may be presumed that in all cases they multiplied by repeated doubling, or occasionally multiplying by 10, and adding the products formed from multipliers that would make up the given multiplier. This is not very different from our modern way, where we multiply by the unit figure of our multiplier, and then by the ten figure, and so on, and then add the