Roman Numerals Conversion

Roman numerals are the symbols that are used in a system of numerical notation based on the ancient Roman system. These numerals are a combination of letters that are used to represent numbers. In this lesson, we will learn how to convert a given number to its Roman numeral and the conversion of Roman numerals to numbers.

Roman numerals for any number are represented using alphabets like I, V, X, and more such letters. We have 7 such Roman numeral conversions which can help us in converting a number to its Roman numeral form.

These basic conversions are helpful to convert any number to its Roman numeral form. 

The following steps show how to convert numbers to Roman numerals:

• Decompose the given number to numbers that can be represented as Roman numerals easily.
• Once the number is decomposed, we can write each decomposed number in its Roman numeral form. 
• The Roman numeral symbols are now written together to obtain the given number in its Roman numeral form.

For example, we can convert 256 to its Roman numeral form in the following way: The number 256 is decomposed as 256 = 200 + 50 + 6. As 200 does not have a symbol, hence, 200 can be split as: 100 + 100. Now, 256 is expressed as: 256 = 100 + 100 + 50 + 6
The Roman numerals for 100, 50, and 6 are represented as C, L, and VI, respectively. Thus, the combined Roman numeral for 256 is: C + C + L + VI = CCLVI

We can also convert a Roman numeral to numbers. The steps to convert Roman numerals to numbers are:

• Write each Roman numeral symbol separately.
• Convert each symbol to its number form and write them separately.
• Add all the numbers to get the number.

Let us understand this using an example.
We can convert CXI to the decimal number form in the following way: Each Roman numeral represents a number. C, X, and I represent 100, 10, and 1, respectively. Now all the numbers are added, CXI = C + X + I = 100 + 10 + 1 = 111. Thus, the Roman numeral CXI represents 111.

Tips to Remember

Here are some points that should be remembered in the Roman numeral conversion:

• When any symbol is written after a larger symbol, it needs to be added to the larger symbol. For example, VII is written as: 5 + 2 = 7.
• When any symbol is written before a larger symbol, it needs to be subtracted from the larger symbol. For example, IX is written as: 10 - 1 = 9.

Topics Related to Roman Numerals Conversions

• Numbers
• Roman Numerals
• Roman Numeral Calculator
• How to Solve Roman Numerals?
• Why Roman Numerals Don't have Number Zero
• Roman Numeral for 5
• Roman Numeral for 100

How to Convert numbers to Roman Numerals?

The following steps show how to convert a number to the Roman numeral form:

• Decompose the given number to those numbers which can be represented as Roman numerals easily.
• Once the number is decomposed, we can write each decomposed number in its Roman numeral form.
• The Roman numeral symbols are now written together to obtain the given number in its Roman numeral form.

For example, 20 can be decomposed to 10 + 10. Now, 10 + 10 can be written together as XX. Thus, the Roman numeral for 20 is XX.

What Does XL Mean in Roman Numerals?

In the Roman numeral form, X is written before L, this indicates that X will be subtracted from L. We know that L = 50, X = 10 which makes it (50 - 10). Hence, XL represents 40 in Roman numerals.

How Do You Write 2020 in Roman Numerals?

2020 can be decomposed as: 2020 = 1000 + 1000 + 10 + 10. Hence, 2020 in Roman numerals is given as, MMXX.

What is 99 in Roman Numerals?

99 is written as, 99 = (100 - 10) + (10 - 1) = XC + IX = XCIX.  Hence, 99 is represented as XCIX in Roman numerals.

What is XLIX in numbers?

We can split XLIX as: XL + IX = (50 - 10) + (10 - 1) = 40 + 9 = 49. Hence, XLIX represents 49 in Roman numerals.