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Last updated on February 28th, 2025

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CMXXVIII in 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 CMXXVIII.

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What is CMXXVIII 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. CMXXVIII in Roman numerals can be written in number form by adding the values of each Roman numeral, i.e., CMXXVIII = 928.

 

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

 

cmxxviii roman numerals

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Basic Rules for CMXXVIII 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 CMXXVIII in Roman Numerals?

Let us learn about how to write CMXXVIII 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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CMXXVIII 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 CMXXVIII,

 

Step 1: First, we break the Roman numerals. CMXXVIII = C + M + X + X + V + I + I + I

 

Step 2: Write the Roman Numerals for each part

The Roman Numeral C is 100

The Roman Numeral M is 1000

The Roman Numeral X is 10

The Roman Numeral V is 5

The Roman Numeral I is 1

 

Step 3: Combine all the numbers M - C + X + X + V + I + I + I = 1000 - 100 + 10 + 10 + 5 + 1 + 1 + 1 = 928.

Therefore, the Roman Numeral CMXXVIII is 928.

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CMXXVIII 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 CMXXVIII.

 

Step 1: The larger Roman numerals are what we will begin with. Once split, the Roman numerals we get are CM, XX, and VIII. The numeral for CM is 900

 

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

Here we add XX and VIII to CM and we will get CMXXVIII. The Roman numeral XX is 20 The Roman numeral VIII is 8 Therefore, the numeral of CMXXVIII is 928.

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Common Mistakes and How to Avoid Them in CMXXVIII Roman Numerals

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CMXXVIII Roman Numerals Examples

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Problem 1

A rare artifact is marked with the inscription CMXXVIII. What is the total if you add CX and CMXXVIII and write the answer in Roman numerals?

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Explanation

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Problem 2

If the year is inscribed as CMXXVIII, how many years ago was it from the year MMXXI? Write the answer in Roman numerals.

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Explanation

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Problem 3

Find the average of numbers represented by CMXXVIII and DCCLVI. Write the result in Roman numerals.

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Explanation

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Problem 4

What is the difference when CMXXVIII is subtracted from MM? Write the answer in Roman numerals.

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Explanation

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Problem 5

Convert the Roman numeral CMXXVIII into its decimal form.

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Explanation

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FAQs on CMXXVIII in Roman Numerals

1.What is CXXVIII in Roman numerals?

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2.Is CMXXVIII a prime number?

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3.What is CMXXVIII + CMXXVIII?

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4.What is MXXVIII?

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5.Subtract XXVIII from CMXXVIII

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Important Glossaries for CMXXVIII in Roman Numerals

  • Subtraction Method: A method used when a smaller numeral precedes a larger numeral, indicating subtraction. For example, CM is 900 (1000 - 100).

 

  • Addition Method: A method used when a larger numeral precedes a smaller numeral, indicating addition. For example, VIII is 8 (5 + 3).

 

  • Repetition Rule: A rule where a numeral is repeated up to three times to increase its value. For example, XXX = 30.

 

  • Place Value: The position of a numeral in a Roman numeral sequence, determining its value. For example, in CMXXVIII, M is in the thousands place.

 

  • Limitation Rule: Some symbols like V, L, and D cannot be repeated. For example, VV for 10 is incorrect; it should be X.
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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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