Last updated on May 26th, 2025
Roman numerals are a 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, use Roman numerals. Have you noticed the names and wondered what these symbols (I and II) represented? Those are Roman numerals. In earlier times, people used fingers, sticks, bones, etc., to count.
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 CLXXX to represent 180, where C is 100, L is 50, and XXX is 30. 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, CLXXX → C + L + X + X + X → 100 + 50 + 10 + 10 + 10 = 180.
Rule 2: Repetition Method
To write a large number, certain Roman numerals can be repeated up to three times. For example, XXX → 30 (X is repeated three times).
Rule 3: Subtraction Method
If a small number is placed before a large number in Roman numerals, we subtract the smaller number from the larger number. For example, IX → X - I → 10 - 1 = 9.
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 LLL for 150; instead, we use CL.
Let’s now learn how to write 180 in Roman numerals. Follow these methods to write the number in Roman numerals.
In the expansion method, based on place value, the number is broken down. In this section, we will learn how to write 180 in Roman numerals using the expansion method.
To write 180 in Roman numerals, follow these steps:
Step 1: Break down the number based on place value: hundreds, tens, ones, etc.
For 180, we write it as 100 + 50 + 30.
Step 2: Convert the numbers into Roman numerals.
100 in Roman numeral — C
50 in Roman numeral — L
30 in Roman numeral — XXX
Step 3: Combine the Roman numerals together.
Therefore, 180 in Roman numerals is C (100) + L (50) + XXX (30) = CLXXX.
When writing a large number in Roman numerals, we group the number.
To write 180 in Roman numerals, we group 180 as 100 + 50 + 30.
100 in Roman numeral — C
50 in Roman numeral — L
30 in Roman numeral — XXX
So, 180 is written as CLXXX in Roman numerals.
Students often make mistakes when writing numbers in Roman numerals. To master Roman numerals, we can learn a few common mistakes and ways to avoid them.
A historian is examining CLXXX ancient coins and wants to evenly distribute them among IX exhibitions. How many coins will each exhibition receive?
Each exhibition will receive XX coins.
To find the number of coins per exhibition, divide the total number of coins by the number of exhibitions.
CLXXX = 180
IX = 9
Therefore, CLXXX / IX = 180 / 9 = 20.
20 in Roman numerals is XX.
An architect is designing a building with CLXXX windows and wants to arrange them in XX rows. How many windows will be in each row?
Each row will have IX windows.
To determine how many windows per row, divide the total number of windows by the number of rows.
CLXXX = 180
XX = 20
Therefore, CLXXX / XX = 180 / 20 = 9.
9 in Roman numerals is IX.
Calculate the sum of XC and XC.
The sum of XC and XC is CLXXX.
Sum is the result of adding two numbers.
XC = 90
XC = 90
90 + 90 = 180
180 in Roman numerals is CLXXX.
A library received a shipment of CCLX books but later found that LXXX books were missing. How many books does the library have now?
The library has CLXXX books.
The difference of two numbers is the value obtained when one number is subtracted from another.
CCLX = 260
LXXX = 80
260 - 80 = 180
180 in Roman numerals is CLXXX.
Write the Roman Numeral for 120 + 60 using the expansion method.
The Roman numeral for 120 + 60 is CLXXX.
Step 1: First convert the numbers 120 and 60 into Roman numerals.
120 - CXX
60 - LX
Add the numbers together: 120 + 60 = 180
Using the expansion method: 180 = 100 + 80 = CLXXX.
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.