Ancient Egyptian Math

So this summer I am taking a class on the History of Mathematics. I find it interesting to see how some of our common mathematical ideas came into being. Did you know that Egyptians had their own form of multiplication? Or that they didn't use fractions as we know them today? The Ancient Egyptians used only "parts" which would be equivalent to our modern "1 over some number." If they had two or more "parts" it was broken down into smaller fractions so that all fractions had a 1 in the numerator. While I find their method of multiplication fun and intriguing, I find their fractions kind of confusing. Further reading revealed that at some point, the Egyptian scribes had written down all the "equivalent parts" in a table for reference. Doing my homework for that particular assignment was a little daunting as I had to change familiar looking fractions into a series of fractions with only 1's in their numerators.

As I mentioned, I actually kind of like their method of multiplication. When I have shown others how to use the Ancient Egyptian method of multiplication, they have all exclaimed how cool that is. Even those people that profess to hate math and claim to not be able to do any math, seem to catch on and LIKE this multiplication method. Simply put, the Ancient Egyptian method involves creating two columns of numbers and doubling the numbers from one row to the next. As an example, if we wanted to multiply 14x15 using the Ancient Egyptian method we would first create two columns. The first column would start with 1 and the second column would start with 15. Then we would double each column so that the next row held the numbers 2 and 30. We continue to double these rows until the next row in the 1 column would be larger than 14. We would add the numbers in the 1 column that sum up to 14 and then add their corresponding numbers from the 15 column. This sum is the answer to our problem. Here's what it would look like:

1            15
2*          30*
4*          60*
8*          120*

Since 2+4+8=14 (I have them marked with an * just to point out which numbers I am adding.), then I would add the corresponding numbers from the other column, 30+60+120=210. Using the traditional method of multiplication I can check my answer and see that 14x15 does equal 210.


The thing about learning the history of mathematics is that sometimes the old ways of doing something can be beneficial to understanding the new ways of doing that same thing. While there are numbers I would not want to multiply using the Ancient Egyptian method, think about trying to use this method to multiply two 3-or4-digit numbers, it is still kind of a cool way to do multiplication. Learning the history of mathematics also helps me to appreciate some of the more modern methods. I know I would not want to memorize an entire table of equivalent parts to use for a fraction. I like math and learning the history behind it, makes me appreciate the nuances and the tricks of mathematics even more.

What does your inner nerd like to learn about?

For anyone interested in learning some history of mathematics, the textbook I am using is: A History of Mathematics: An Introduction by Victor J. Katz. I found my copy on Amazon.com.