178 LearnersLast updated on May 26th, 2025
CMXVII in Roman Numerals
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 CMXVII.
What is CMXVII 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. CMXVII in Roman numerals can be written in number form by adding the values of each Roman numeral, i.e., CMXVII = 917.
Let us learn more about the Roman numeral CMXVII, how we write them, the mistakes we usually make, and ways to avoid these mistakes.
Basic Rules for CMXVII 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 smaller symbol precedes a larger 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.
How to Write CMXVII in Roman Numerals?
Let us learn about how to write CMXVII in Roman numerals. There are two methods that we can use to write Roman numerals:
- By Expansion Method
- By Grouping Method
CMXVII 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 CMXVII,
Step 1: First, we break the Roman numerals. CMXVII = C + M + X + V + 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 C (1000 - 100) + X (10) + V (5) + I + I = 900 + 10 + 5 + 1 + 1 = 917. Therefore, the Roman Numeral CMXVII is 917.
CMXVII 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 CMXVII.
Step 1: The larger Roman numerals are what we will begin with. Once split, the Roman numerals we get are CM, X, and VII. 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 X and VII to CM, and we will get CMXVII. The Roman numeral X is 10. The Roman numeral VII is 7. Therefore, the numeral of CMXVII is 917.
Numbers Related to CMXVII in Roman Numerals
We follow a pattern when it comes to writing Roman numerals. In this section, we will write some numbers related to the Roman numeral CMXVII:
| Roman Numeral | Number | Breakdown |
|---|---|---|
| CMXI | 911 | CM + X + I |
| CMXII | 912 | CM + X + I + I |
| CMXIII | 913 | CM + X + I + I + I |
| CMXIV | 914 | CM + X + IV |
| CMXV | 915 | CM + X + V |
| CMXVI | 916 | CM + X + V + I |
| CMXVII | 917 | CM + X + V + I + I |
| CMXVIII | 918 | CM + X + V + I + I + I |
| CMXIX | 919 | CM + X + IX |
| CMXX | 920 | CM + XX |
Common Mistakes and How to Avoid Them in CMXVII Roman Numerals
Students can make mistakes when studying Roman numerals. Here are a few common mistakes students make, and ways to avoid them.
Mistake 1
Mistakes when applying the repetition method
It can be quite confusing for beginners to remember that Roman Numerals cannot be repeated more than three times. Another thing to keep in mind is that Roman Numerals such as V, L, and D cannot be repeated.
For example, writing LL as 100 is incorrect; the correct answer is C.
Mistake 2
Not subtracting the numerals correctly
The subtraction method is used when a smaller symbol precedes a larger symbol. One should also remember that only specific symbols can be subtracted, like I and X.
For example, IL instead of XLIX for the number 49.
Mistake 3
Not grouping the numbers correctly.
When writing Roman numerals, we need to group the numbers correctly.
For example, the number 15, 10(X) + 5(V).
Mistake 4
Confusing similar-looking symbols for other numbers
Certain numerals have different numbers when placed in a different order. So we must make sure to fully understand the order of certain symbols and their placements. All symbols have to be placed in a different order to represent the correct number.
For example, IV (4) and VI (6) have the same symbols but are in different orders.
Mistake 5
Not counting all numbers when writing in Roman numerals.
Forgetting to count all numbers when doing the expansion method or grouping method can lead to mistakes.
For example, writing CMX (910) and forgetting VII (7) for 917. Recheck steps once done during any arithmetic operation.
CMXVII Roman Numerals Examples
Problem 1
What is the sum of CMXVII and LXXXIII? Write the answer in Roman numerals.
The sum is M
Explanation
Convert both Roman numerals into their decimal forms:
CMXVII = 917
LXXXIII = 83
Now add both numbers: 917 + 83 = 1000
Now convert the number into its Roman numeral: 1000 = M
Problem 2
Subtract CCCXV from CMXVII and express the result in Roman numerals.
The result is DCII
Explanation
Convert the Roman numerals into their decimal forms:
CMXVII = 917
CCCXV = 315
Now subtract the numbers: 917 - 315 = 602
Convert the number into its Roman numeral: 602 = 600 (DC) + 2 (II) = DCII
Problem 3
Multiply CMXVII by II and write the answer in Roman numerals.
MDCCCXXXIV
Explanation
Convert CMXVII into its decimal form:
CMXVII = 917
Multiply by 2: 917 × 2 = 1834
Convert 1834 into its Roman numerals: 1000 (M) + 800 (DCCC) + 30 (XXX) + 4 (IV) = MDCCCXXXIV
Problem 4
Divide CMXVII by VII and express the answer in Roman numerals.
CXXXI
Explanation
Convert CMXVII into its decimal form:
CMXVII = 917
Divide by 7: 917 / 7 = 131
Convert 131 into its Roman numerals: 100 (C) + 30 (XXX) + 1 (I) = CXXXI
Problem 5
Convert CMXVII into its decimal form.
In decimal form, CMXVII is 917
Explanation
Break CMXVII into components:
CM = 900 (1000 - 100)
XVII = 17 (10 + 5 + 1 + 1)
Add values: 900 + 17 = 917
FAQs on CMXVII in Roman Numerals
1.What is XVII in Roman numerals?
2.Is CMXVII a prime number?
3.What is CMXVII + CMXVII?
4.What is MCMXVII?
5.Subtract XVII from CMXVII
6.How can children in India use numbers in everyday life to understand CMXVII in Roman Numerals?
7.What are some fun ways kids in India can practice CMXVII in Roman Numerals with numbers?
8.What role do numbers and CMXVII in Roman Numerals play in helping children in India develop problem-solving skills?
9.How can families in India create number-rich environments to improve CMXVII in Roman Numerals skills?
Important Glossaries for CMXVII in Roman Numerals
- Limitation Rule: There are some symbols that cannot be repeated more than once (V, L, D). For example, writing VV for 10 is wrong; the correct answer is X.
- Subtraction Rule: When a smaller numeral precedes a larger numeral, the smaller one is subtracted. For example, IV is 4 (5 - 1).
- Addition Rule: When a smaller numeral follows a larger numeral, the numerals are added. For example, VI is 6 (5 + 1).
- Place Value: The position of a digit in a number determines its value. For example, the number 9 in 917 is in the hundred's place.
- Numerical Expansion: The process of breaking down Roman numerals into their constituent parts to find their equivalent numeric value.
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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.
Fun Fact
: She loves to read number jokes and games.
