Roman Numerals

The Romans had a way for joining symbols together to make big numbers which is still used today on some clock faces, and you’ll see it on some BBC programmes where they show the year it was made. In this system, every letter stands for a number. I = one,
V = five, X = ten, L = fifty C = a hundred, D = five hundred and
M = one thousand.

It may seem tricky at first, but all you have to learn is seven symbols and just one rule, and you can untangle even the most complicated year. The rule is: if a symbol for a small number is put before the symbol for a big number instead of after it, then you take the small number away from the big one.

I like to remember 400 because it is CD. You know I is one and V is five. You probably know X is 10. If you know what a millenium is you only have to learn that L is 50 and you know all the Roman numerals. MMIX is two M’s which are a thousand each, and a I (one) which we take away from the X (ten) because it comes before the X. That’s two thousands and nine = 2009. You may see MMIX on TV if it is this year’s programme.

Try one yourself: What is MCMXCIX? I'll let you know next time.

That sums it up.