### If you take a close look at the world, you’ll find that you’re surrounded by ancient history. There are lots of great examples of this, but today we’re going to talk about one example in particular that’s near and dear to my—and hopefully your—mathematical heart: Roman numerals. These ancient numbers can still be seen all over the place—on signs, clocks, monuments, and even in movie credits! But who came up with this number system? Was it really the Romans? How exactly does it work? And why is it still used for certain things? Stay tuned because those are precisely the questions we’ll be answering today.

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## How to Read and Write Roman Numerals

### Second, you need to know that just like in the Egyptian hieroglyphic system, numbers are written by combining symbols together. For example, the number 3 is written “III” (since that’s 1+1+1), the number 7 is written “VII” (since that’s 5+1+1), the number 61 is written “LXI” (since that’s 50+10+1), and so on. The last thing you need to know is that if a smaller value is written before a larger value—something like “IV” where the symbol for 1 is written before the symbol for 5—that means that the smaller value should be subtracted from the larger value. So “IV” represents 5 – 1 = 4 and “IX” represents 10 – 1 = 9.

You only need to know a few things to become a Roman numeral expert.