# Roman Numeral Calculator

To use the Roman number calculator, Select the arithmetic operation, enter the two values into their designated boxes, and Click Calculate.

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## Roman numeral Calculator

Roman numeral calculator is an arithmetic tool that performs basic mathematical operations on numbers; the numbers are Roman and not decimal

## What are Roman Numerals?

Roman numerals are a number system originating from ancient Rome. They use combinations of letters from the Latin alphabet to represent values. Here are the basic symbols and the values they represent:

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

### Rules for constructing numbers with Roman numerals:

• Repeating a numeral up to three times represents the addition of the number. For instance, III = 3.
• Only one smaller number may be placed to the left of a larger number to indicate subtraction. For instance, IV = 4 (5 - 1) and IX = 9 (10 - 1).
• If a numeral is placed after a larger or equal numeral, it is added. For instance, VI = 6 (5 + 1) and XX = 20 (10 + 10).

In the subtraction cases, the smaller numeral must be I, X, or C. The larger numeral must be a numeral with a value no more than 10 times larger than the smaller numeral. I can be subtracted only from V and X. X can be subtracted only from L and C. C can be subtracted only from D and M.

So using these rules, here are some examples:

• II = 2
• VII = 7
• XII = 12
• XXVII = 27
• XC = 90
• CIII = 103
• MCMXCVI = 1996
• MMXXIII = 2023

This system does not have a concept of zero and does not use the place-value system, which makes it quite different from the decimal numeral system, which is widely used today.

## How to perform arithmetic operations on Roman numerals?

Performing operations on Roman numerals is very tricky and time-consuming. This is why they are first converted to decimal numbers and then the result is converted to Roman numerals.

Let's add XII (12) and XVI (16).

Convert to decimal numerals: 12 + 16 = 28

Convert back to Roman numerals: 28 = XXVIII

So, XII + XVI = XXVIII.

1. Subtraction

Subtract XVI (16) from XX (20).

Convert to decimal numerals: 20 - 16 = 4

Convert back to Roman numerals: 4 = IV

So, XX - XVI = IV.

1. Multiplication and Division

For example, to multiply III (3) by IV (4):

Convert to decimal numerals: 3 * 4 = 12

Convert back to Roman numerals: 12 = XII

So, III * IV = XII.

It's important to note that while it's possible to do these operations using Roman numerals, it's not how they were historically used. The Romans did not use these methods; instead, they would have used other techniques, like the use of an abacus, to perform arithmetic operations.

## Table for Roman numerals:

 Roman numerals Decimal number I 1 II 2 III 3 IV 4 V 5 VI 6 VII 7 VII 8 IX 9 X 10 XX 20 XXX 30 XL 40 L 50 LX 60 LXX 70 LXXX 80 XC 90 C 100 CD 400 D 500 CM 900 M 1000