Roman Numerals

[RTFishall]

How did the Romans manage to multiply and divide with their numbering system?

[dove]

I dont think they could, thats why it changed to what we use today.

[dundurn]

I believe they used what we would now call a ready reckoner, i.e. you put numbers along the top and left hand side of a square and the products of those numbers where the row and column intersect. By usig the square "in reverse" you can make it work for division as well but you end up with a fraction or a remainder rather than a decimal answer.

[heathfield]

Multiplication is covered here. It seems pretty straightforward, (if you were used to doing it!).

[dove]

just wanted to get all four lol
sorry

[jno]

they knew how to use the abacus. They're still used in the far east, and shopkeepers can do their sums faster than I can on a calculator