Did the Egyptiansuse fractions?
Yes, the Egyptian numbering system dealt with fractions, albeit with symbols that do
not resemble modern notation. Fractions were written by placing the hieroglyph for
“mouth” over the hieroglyph for the numerical expression. For example, 1/5 and 1/10
would be seen as the first two illustrations represented in the box on p. 15. Other frac-
tions, such as the two symbols for 1/2 (see illustration on p. 15), also have special signs.
What were the problemswith the Egyptian number system?
The Egyptian number system had several problems, the most obvious being that it
was not written with certain arithmetic calculations in mind. Similar to Roman 13
HISTORY OF MATHEMATICS
What are some examples of Egyptian multiplication?
E
gyptian multiplication methods did not require a great deal of memorization,
just a knowledge of the two times tables. For a simple example, to multiply
12 times 16, they would start with 1 and 12. Then they would double each num-
ber in each row (1 2 and 12 2; 2 2 and 24 2; and so on) until the num-
ber 16, resulting in the answer 192:
112
224
448
896
16 192
Another example computes a number that is not a multiple in the row, such
as 37 times 19:
119
238
476
8 152
16 304
32 608
First, do the usual procedure by starting with 1 and 19, then doubling the
numbers until you get to 32 (if you double 32 [64], you’ve overshot the num-
ber 37). Because 37 is higher than 32, go back over the list on the left-hand side,
figure out which numbers, with 32, add up to 37 (1, 4, and 32); then add the
numbers that correspond to those numbers, to the right (19, 76, and 608),
which equals the answer: 703. And you didn’t even need a calculator!