Last updated on May 26th, 2025
Roman numerals are the way of expressing numbers using symbols. I, V, X, L, C, D, and M are the symbols we use. Roman numerals are used in royal titles, book names, sequences, and so on. Here we will be discussing Roman numerals, rules, and examples.
The royal titles, such as Henry I, Henry II, and so on. Have you noticed the names and wondered what these symbols (I and II) represented? Those are the Roman numerals. Earlier people used to count using fingers, sticks, bones, etc. When life became complex, a standard form was required to count. Ancient Romans used the Roman numeral system to count. I (1), V (5), X (10), L (50), C (100), D (500), and M (1000) are the symbols we use to count.
In Roman numerals, we use CCCLI to represent 351, where CCC is 300, L is 50, and I is 1. Let’s learn more about Roman numerals and how we write them.
There are certain basic rules to write a number in Roman numerals. In this section, let’s discuss some basic rules that need to be remembered when writing a number in Roman numerals.
Rule 1: Addition Method
The addition method is used when the smaller number is placed after the larger number. For example, LI → L + I → 50 + 1 = 51.
Rule 2: Repetition Method
To write a large number, certain Roman numerals can be repeated up to three times. CCC → 300.
Rule 3: Subtraction Method
If a small number is followed by a large number in Roman numerals, we subtract the smaller number from the large number. For example, XL → L - X → 50 - 10 = 40.
Rule 4: Limitation Rule
The symbols cannot be repeated more than three times, and some symbols like V, L, and D cannot be repeated. For example, we won't write LL for 100; instead, we use C, and 9 is written as IX, not VIIII.
Let’s now learn how to write 351 in Roman numerals. Follow these methods to write the number in Roman numerals.
By Expansion Method
By Grouping Method
In the expansion method, based on place value, the number is broken down. In this section, we will learn how to write 351 in Roman numerals using the expansion method.
To write 351 in Roman numerals, follow the steps:
Step 1: Break the number based on place value. Place values are ones, tens, hundreds, etc.
For 351, we write it as 300 + 50 + 1.
Step 2: Convert the number into Roman numerals:
300 in Roman numerals — CCC
50 in Roman numerals — L
1 in Roman numerals — I
Step 3: Combine the Roman numerals together.
Therefore, 351 in Roman numerals is CCC (300) + L (50) + I (1) = CCCLI.
When writing a large number into Roman numerals, we group the number.
To write 351 in Roman numerals, we group 351 as 300 + 50 + 1.
300 in Roman numerals — CCC
50 in Roman numerals — L
1 in Roman numerals — I
So, 351 is written as CCCLI in Roman numerals.
Students make mistakes when writing a number in Roman numerals. To master Roman numerals, we can learn a few common mistakes and ways to avoid them.
A historian is cataloging ancient artifacts and finds a collection of artifacts labeled CL and CXLI. What is the combined total of these artifacts in Roman numerals?
The combined total of CL and CXLI is CCCXCI.
To find the total, you add the two numbers together.
CL = 150
CXLI = 141
150 + 141 = 291
291 in Roman Numerals is CCXCI.
Therefore, the combined total of CL and CXLI is CCXCI.
An architect is designing a museum with a total floor area of DCCLXXXV square meters, divided equally into XXV rooms. How many square meters is each room?
Each room has XXXI square meters.
To find the area of each room, divide the total area by the number of rooms.
DCCLXXXV = 785
XXV = 25
785 / 25 = 31
31 in Roman Numerals is XXXI.
Each room has XXXI square meters.
A mathematician is examining patterns in numbers and calculates the sum of CLXXV and CLXXVI. What is the result in Roman numerals?
The sum of CLXXV and CLXXVI is CCCLI.
Sum is the result of adding two numbers.
CLXXV = 175
CLXXVI = 176
175 + 176 = 351
351 in Roman Numerals is CCCLI.
The sum of CLXXV and CLXXVI is CCCLI.
What is the difference between CD and XLIX?
The difference between CD and XLIX is CCCLI.
The difference is found by subtracting one number from the other.
CD = 400
XLIX = 49
400 - 49 = 351
351 in Roman Numerals is CCCLI.
The difference between CD and XLIX is CCCLI.
Write the Roman Numeral for 200 + 151 using the expansion method.
The Roman numeral for 200 + 151 is CCCLI.
Step 1: Convert the numbers 200 and 151 into Roman numerals.
200 - CC
151 - CLI
Add the numbers together: 200 + 151 = 351
Using the expansion method: 351 = 300 + 50 + 1 = CCCLI
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.
: She loves to read number jokes and games.