Greeks had a variety
of different ways of writing down numbers, but none of them was very
efficient. (And of course different Greek city-states
used somewhat different systems, too).
Some Greeks used a system based on writing the first letter of the word for that number. Like in Greek you say Ten “Deka”, so they would draw a D to mean 10. (A delta, actually, in the Greek alphabet).In this system though,1 was just written with a vertical line, like our 1 today. They used P for Pente (five), D for deka (ten), H for Hekaton (100), X for Xhilioi (1000), and M for Murioi (10,000). So you could write 539 as HHHHHDDDPIIII. But this was pretty hard to read.
To make it a little easier, they also combined these symbols to make special symbols for 50, 500, 5000, and 50,000.
The Greeks also used another system where the letters
of the Greek alphabet each
stood for a number, so 1 was alpha (A), 2 was beta (B), 3 was gamma
(G) and so forth. (The letters in the Greek alphabet were not in exactly
the same order as in English).
They did this for the first ten letters, and then the 11th letter stood for 20, the 12th letter stood for 30, the 13th letter stood for 40, and so on. After 100 the next letter stood for 200 and so forth. This system was more efficient to write.
But neither one of these systems was any good for adding or multiplying long strings of numbers, like if you wanted to keep accounts in a store. For that, the number system of India (invented around 600 AD) was much better - the system we use today is based on that.
To find out more about ancient numbers, check out this book from Amazon.com or from your library:
Can You Count in Greek - Exploring Ancient Number Systems, by Judy Leimbach (1990). Includes the Roman, Babylonian, Egyptian and Mayan number systems too, with lots of math activities for kids.