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Last updated on March 2nd, 2025

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MCMXC Roman Numerals

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Intermediate
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To meet their daily commerce and administration needs, the ancient Romans developed Roman Numerals. It used a combination of seven symbols — I, V, X, L, C, D, and M to represent numbers. Roman numerals were used to record transactions, keep track of data, and label military units. In this topic, we are going to learn about the Roman numeral MCMXC.

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What is MCMXC in Roman Numerals?

Ancient Romans discovered that counting fingers could get very complicated after 10. So to overcome the complexity, the Roman numeric system was developed. This was widely used throughout Europe as a standard writing system until the late Middle Ages.

 

Seven symbols are used to represent numbers in the Roman numeric system — I, V, X, L, C, D, and M. The numerals are made up of different combinations of these symbols. MCMXC in Roman numerals can be written in number form by adding the values of each Roman numeral, i.e., MCMXC = 1990.

 

Let us learn more about the Roman numeral MCMXC, how we write it, the mistakes we usually make, and ways to avoid these mistakes.

 

mcmxc roman numerals

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Basic Rules for MCMXC in Roman Numerals

When writing Roman numerals, there are a few rules that we need to follow based on the Roman numerals we are trying to write. In this section, we will learn about the rules when writing Roman numerals and how to represent them.

 

Rule 1: Addition Method:

When a larger symbol is followed by a smaller symbol, we add the numerals to each other. For example, in VIII, we have 5 + 3 = 8.

 

Rule 2: Repetition Method:

A symbol that is repeated three times in continuation increases the value of the numeral. For example, XXX = 30.

 

Rule 3: Subtraction Method:

We use the subtraction method when a larger symbol follows a smaller symbol. For example, XL = 40 (which is 50 – 10).

 

Rule 4: Limitation Rule:

Symbols cannot be repeated more than three times, and some symbols, such as V, L, and D cannot be repeated more than once. For example, 10 is represented as X and not VV.

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How to Write MCMXC in Roman Numerals?

Let us learn about how to write MCMXC in Roman numerals. There are two methods that we can use to write Roman numerals:

 

  • By Expansion Method
  • By Grouping Method
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MCMXC in Roman Numeral by Expansion Method

The breaking down of Roman numerals into parts and then converting them into numerals is what we call the expansion method. The expansion method is the breaking down of Roman numerals into numerical form and adding them to get the final number.

 

Step 1: Break the Roman numerals into parts.

 

Step 2: Now write each of the Roman numerals with its numerical digit in the place value.

 

Step 3: Add the numerals together.

 

For MCMXC,

 

Step 1: First we break the Roman numerals. MCMXC = M + CM + XC

 

Step 2: Write the Roman Numerals for each part The Roman Numeral M is 1000 The Roman Numeral CM is 900 The Roman Numeral XC is 90

 

Step 3: Combine all the numbers M + CM + XC = 1000 + 900 + 90 = 1990. Therefore, the Roman Numeral MCMXC is 1990.

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MCMXC in Roman Numeral by Grouping Method

Using subtraction and addition rules, we will apply the grouping method. This means we break the Roman numerals into smaller groups, which makes it easier to work with. This method groups the Roman numerals logically, and then we write the numbers for each group.

 

Step 1: Take the largest number and write the number for that Roman numeral.

 

Step 2: Write the Roman numeral using the subtraction and addition rules.

 

Example: Let’s take the Roman numeral MCMXC.

 

Step 1: The larger Roman numerals are what we will begin with. Once split, the Roman numerals we get are M, CM, and XC. The numeral for M is 1000

 

Step 2: Now we need to either add or subtract the smaller number, depending on its place.

 

Here we add CM and XC to M and we will get MCMXC. The Roman numeral CM is 900 The Roman numeral XC is 90 Therefore, the numeral of MCMXC is 1990.

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Common Mistakes and How to Avoid Them in MCMXC Roman Numerals

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MCMXC Roman Numerals Examples

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Problem 1

Calculate the product of MCMXC and II. Write the answer in Roman numerals.

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Explanation

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Problem 2

Subtract CMX from MCMXC and express the result in Roman numerals.

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Explanation

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Problem 3

Divide MCMXC by V and write the answer in Roman numerals.

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Explanation

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Problem 4

Add MCMXC and DCCCXL and give the answer in Roman numerals.

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Explanation

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Problem 5

Convert MCMXC into its decimal form.

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Explanation

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FAQs on MCMXC in Roman Numerals

1.What is CMXC in Roman numerals?

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2.Is MCMXC a prime number?

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3.What is MCMXC + MCMXC?

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4.What is MMCMXC?

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5.Subtract XC from MCMXC

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Important Glossaries for MCMXC in Roman Numerals

  • Addition Method: A method where numerals are added together when a smaller numeral follows a larger numeral.

 

  • Subtraction Method: A method where a numeral is subtracted from another when a smaller numeral precedes a larger numeral.

 

  • Place Value: The position of a digit in a number, this position determines its value. For example, the number 9 in 1990 is in the tens place.

 

  • Limitation Rule: Some symbols cannot be repeated more than once (V, L, D). For example, writing VV for 10 is incorrect; the correct numeral is X.

 

  • Roman Numerals: A numeric system used in ancient Rome, employing combinations of letters from the Latin alphabet (I, V, X, L, C, D, M).
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Hiralee Lalitkumar Makwana

About the Author

Hiralee Lalitkumar Makwana has almost two years of teaching experience. She is a number ninja as she loves numbers. Her interest in numbers can be seen in the way she cracks math puzzles and hidden patterns.

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Fun Fact

: She loves to read number jokes and games.

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