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### Memory Aid for Roman Numerals

```
Date: 05/10/2000 at 18:54:40
From: MLC
Subject: Roman Numerals

What number is XLIII? I need the standard version. Also, do you have a
way of remembering what letter equals what number?
```

```
Date: 05/11/2000 at 02:01:24
From: Doctor Jesse
Subject: Re: Roman Numerals

The simple rules for Roman numerals:

I = 1
V = 5
X = 10
L = 50
C = 100
D = 500
M = 1000

To translate Roman numerals to Arabic numerals (the ones we use),

If a smaller numeral comes before a larger numeral, subtract the small
one from the large one. Otherwise, just add up the numbers.

So:

VII = 5 + 1 + 1 = 7
CLXIII = 100 + 50 + 10 + 1 + 1 + 1 = 163

But:

IX = (10 - 1) = 9
XLV = (50 - 10) + 5 = 45

Based on that info, you should be able to figure out your number,
XLIII.

Good luck!

PS: Here's a memorization tip: Most people can remember the values for
I, V, and X. L, C, D, and M are harder to remember. An easy way is to
remember the name of the famous Vietnamese cow: Elsie Diem. If you can
remember that, you will always remember L-C-D-M! I know it's corny,
but it works!

- Doctor Jesse, The Math Forum
http://mathforum.org/dr.math/
```
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