The Romans used several different systems for writing numbers. Sometimes they wrote numbers like this: I II III IV V and other times they used the
Greek numbers. The Roman numbers were not always written the same way, either - people knew what you meant even if you did it a little differently. Here's a table showing all of the Roman numerals.
I
| 1
|
| L
| 50
|
II
| 2
|
| C
| 100
|
III
| 3
|
| D
| 500
|
IV (or IIII)
| 4
|
| M
| 1000
|
V
| 5
|
|
|
|
VI
| 6
|
|
|
|
VII
| 7
|
|
|
|
VIII
| 8
|
|
|
|
IX (or VIIII)
| 9
|
|
|
|
X
| 10
|
|
|
|
So MMIII is 2003, and XXIV is 24, and CLVII is 157. (Putting a bigger number like V after a smaller number like I means "1 less than 5" or 4).
Roman numbers, these numbers would look like this:
314 = CCCXIV
26 = XXVI
1975 = MCMLXXV
2010 = MMX
What problems do you think this would cause for Roman children who were learning to multiply and divide, or even to add large numbers? Would you be able to borrow or carry using these numbers? Why or why not?
In fact, because it was so hard, Roman children, even the ones who went to school, didn't learn to multiply or divide big numbers on paper. They memorized their times tables, like you. For larger numbers, they learned to use a counting board, or an abacus. But a lot of multiplication and division was done by looking up the answer in a table, and most of it was done by specially trained experts, not by ordinary people.
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