How to Convert a Number to Roman Numerals
The Roman numeral system is a counting system that was devised by the ancient inhabitants of the Italian peninsula. The Roman system was gradually replaced by the base-10 Arabic numeral system we use today, since it made scientific and mathematical calculations much easier. Today, Roman numerals are used mainly for stylistic and decorative effects.
If you want to express a number using roman numerals, use the steps below.
- Difficulty:
- Moderate
Instructions
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1
roman numerals
We'll use the number 75493 as our example to illustrate each step. First, memorize or refer to the list at left. In the Roman numeral system, the basic "digits" are the letters I, V, X, L, C, D, and M which represent 1, 5, 10, 50, 100, 500, and 1000 respectively.
To represent the numbers 5000, 10000, 50000, 100000, 500000, and 1000000, you use the letters V, X, L, C, D, and M with a horizontal bar over the top.
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2
Separate the digits of your number into 1's, 10's, 100's, etc. Start with the 1's digit. The table at left shows you how to represent the digits 1 through 9. Since our last digit is 3, we write III.
The logic behind the Roman numeral system is that you represent 1, 2, and 3 and 5 by I, II, III, and V. Since 4 is one less than 5, 4 = IV.
Since 6 is one more than 5, 6 = VI. And thus 7 = VII and 8 = VIII as well.
Since 9 is one less than ten, we write 9 = IX.
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3
Now move on to the 10's digit. 10, 20, and 30 are X, XX, and XXX respectively. 50 is L, and since 40 is ten less than fifty, 40 = XL
60, 70, and 80 are written as LX, LXX, and LXXX in Roman numerals. And since 90 is ten less than a hundred, 90 = XC.
This is analogous to the pattern for the 1's digits. Since the tens digit is 9 in our example, we write XC.
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4
Repeat the pattern for the 100's digit, using the guide at left. Since the 100's digit is 4 in our example, we write CD.
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5
For the 1000's digit, the pattern is the same as above, except now we need to use the horizontal bar. In our example, the 5 will be represented as a V with a line over it.
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6
Lastly, the 7 in the 10000's place will be represented by LXX with a line over every letter.
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7
Finally, putting all 5 pieces together, the Roman numeral representation of 75493 is shown in the image.
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