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. Have you noticed the names and wondered what these symbols (I and II) represented? Those are the Roman Numerals.
Earlier, people used fingers, sticks, bones, etc., to count. When life became complex, a standard form was required. 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 CMXI to represent 911, where CM is 900, X is 10, 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.
The addition method is used when the smaller number is placed after the larger number. For example, XI → X + I → 10 + 1 = 11.
To write a large number, certain Roman Numerals can be repeated up to three times. For example, III → 3.
If a small number is placed before a large number in Roman Numerals, we subtract the smaller number from the large number. 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 8 is written as VIII, not IIIIIIII.
Let’s now learn how to write 911 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 911 in Roman numerals using the expansion method. To write 911 in Roman Numerals, follow the steps:
Step 1: Break the number based on the place value: hundreds, tens, and ones. For 911, we write it as 900 + 10 + 1.
Step 2: Convert the numbers into Roman Numerals.
Step 3: Combine the Roman Numerals together. Therefore, 911 in Roman Numerals is CM (900) + X (10) + I (1) = CMXI.
When writing a large number into Roman Numerals, we group the number. To write 911 in Roman Numerals, we group 911 as 900 + 10 + 1.
So, 911 is written as CMXI 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 a manuscript claiming that the Romans built CMXI aqueducts. How many aqueducts is this in modern numbers?
The number of aqueducts is 911.
The Roman numeral CMXI represents 911.
C = 100,
M = 1000,
X = 10,
I = 1.
CM = 900,
plus X = 10,
plus I = 1,
which equals 911.
During an archaeological dig, a researcher finds a Roman coin marked with the year DCCCCXI. Convert this year into the Gregorian calendar.
The year DCCCCXI is 911 in the Gregorian calendar.
The Roman numeral DCCCCXI translates to 911
D = 500,
C = 100,
X = 10,
I = 1.
DCCC = 800,
plus CX = 110,
plus I = 1, equals 911.
An ancient Roman document describes a festival held every X years. If the festival was last held in year CMXI, when will the next festival occur?
The next festival will occur in year CMXXI.
CMXI is 911, and the festival occurs every 10 years (X in Roman numerals).
Therefore, the next festival will be in 911 + 10 = 921, which is CMXXI in Roman numerals.
A museum has a collection of artifacts numbered from I to CMXI. How many artifacts are there in total?
There are 911 artifacts in total.
The Roman numeral CMXI represents 911.
Therefore, there are 911 artifacts numbered sequentially from I to CMXI.
A researcher is cataloging an ancient library and finds a record of CMXI scrolls. Convert this number to understand how many scrolls there are.
There are 911 scrolls.
CMXI in Roman numerals stands for 911.
C = 100,
M = 1000,
X = 10,
I = 1.
CM = 900,
plus X = 10,
plus I = 1,
totaling 911 scrolls.
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.