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. to count earlier. 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), D (100), and M (1000) are the symbols we use to count.
In Roman Numerals, we use CLVII to represent 157, where C is 100, L is 50, V is 5, and II is 2. 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.
The addition method is used when the smaller number is placed after the larger number. For example, CLVII → C + L + V + II → 100 + 50 + 5 + 2 = 157
To write a large number, there are certain Roman Numerals that can be repeated three times. III → 3.
If a small number is followed by a large number in Roman Numerals, we subtract the smaller number from the large number, it is a subtraction method. For example, IX → X - I → 10 - 1 = 9
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 VV for 10; instead, we use X, and for 8, we write VIII, not IIIIIIII.
Let’s now learn how to write 157 in Roman Numerals. Follow these methods to write the number in Roman Numerals.
In the expansion method, based on the place value, the number is broken down. In this section, we will learn how to write 157 in Roman numerals using the expansion method.
To write 157 in Roman Numerals, follow the steps,
Step 1: The number is broken based on the place value. Place values are ones, tens, hundreds, etc.
For 157, we write it as 100 + 50 + 5 + 2.
Step 2: Converting the number into Roman Numerals
- 100 in Roman Numeral — C
- 50 in Roman Numeral — L
- 5 in Roman Numeral — V
- 2 in Roman Numeral — II
Step 3: Combining the Roman Numerals together.
Therefore, 157 in Roman Numeral is C (100) + L (50) + V (5) + II (2) = CLVII
When writing a large number into Roman Numeral, we group the number.
To write 157 in Roman Numeral, we group 157 as 100 + 50 + 5 + 2.
- 100 in Roman Numeral — C
- 50 in Roman Numeral — L
- 5 in Roman Numeral — V
- 2 in Roman Numeral — II
So, 157 is written as CLVII 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 the ways to avoid them.
A historian discovers CLVII ancient coins buried in the ground and decides to distribute them equally among VII treasure chests. How many coins will each chest contain?
Each chest will contain XXIII coins.
To find how many coins each chest gets, divide the total number of coins by the number of chests.
CLVII = 157
VII = 7
157 ÷ 7 = 22.428..., but rounded down, each chest will contain 22 coins, represented as XXII in Roman numerals.
(Note: Due to divisibility, CLVII is not perfectly divisible by VII in this context unless rounded.)
A researcher wants to analyze data points from two sets. The first set contains CXV data points, and the second contains XLII. What is the total number of data points in both sets?
The total number of data points is CLVII.
To find the total, add the data points from both sets.
CXV = 115
XLII = 42
115 + 42 = 157
157 in Roman numerals is CLVII.
A library decides to acquire a collection of books in two phases. In the first phase, they acquire LXXX books, and in the second phase, they acquire LXXVII books. How many books did the library acquire in total?
The library acquired CLVII books in total.
Add the books acquired in both phases to find the total.
LXXX = 80
LXXVII = 77
80 + 77 = 157
157 in Roman numerals is CLVII.
An architect designs a building with a total of CLVII windows. If each floor contains X windows, how many full floors can be built with the allocated windows?
XV full floors can be built.
To find the number of full floors, divide the total windows by the number of windows per floor.
CLVII = 157
X = 10
157 ÷ 10 = 15.7. Therefore, XV full floors can be constructed.
Convert the sum of XLIX and CVIII into Roman numerals using the expansion method.
The Roman numeral for the sum is CLVII.
First, convert the numbers to Roman numerals and add them.
XLIX = 49
CVIII = 108
49 + 108 = 157
Using the expansion method: 157 = 100 + 50 + 7 = CLVII
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.