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 to count using 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 DCCXC to represent 790, where D is 500, CC is 200, X is 10, and C is 100. 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, DCCXC → D + CC + X + C → 500 + 200 + 10 + 100 = 790
To write a larger number, certain Roman Numerals can be repeated up to three times. For example, CCC → 300.
If a smaller number is followed by a larger number in Roman Numerals, we subtract the smaller number from the larger number. For example, XC → C - X → 100 - 10 = 90
The symbols cannot be repeated more than three times, and some symbols like V, L, and D cannot be repeated. For example, we don't write DDD for 1500; instead, we use MD.
Let’s now learn how to write 790 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 790 in Roman numerals using the expansion method.
To write 790 in Roman Numerals, follow the steps:
Step 1: Break the number based on the place value: hundreds, tens, and ones. For 790, we write it as 700 + 90
Step 2: Convert the number into Roman Numerals:
Step 3: Combine the Roman Numerals together. Therefore, 790 in Roman Numerals is DCC (700) + XC (90) = DCCXC
When writing a large number in Roman Numerals, we group the number. To write 790 in Roman Numerals, we group 790 as 700 + 90
So, 790 is written as DCCXC 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.
Convert the year DCCXC to a modern calendar year and find out how many years have passed since then.
The year DCCXC is 790. As of 2023, 1233 years have passed.
First, convert the Roman numeral DCCXC to a modern number.
DCCXC is 790.
Subtract 790 from the current year, 2023.
2023 - 790 = 1233.
Therefore, 1233 years have passed since the year 790.
A museum decides to organize exhibitions for DCC students each year over X years. How many students will visit the museum in total?
A total of 7900 students will visit the museum over 10 years.
To find the total number of students visiting the museum, multiply the number of students per year by the number of years.
DCC = 700 and X = 10.
Therefore, 700 × 10 = 7000.
7000 students will visit the museum over the course of 10 years.
A collection of ancient coins includes DCCXC silver coins, and CCCXXV of them are Roman denarii. How many coins are not denarii?
There are CDLXV coins that are not denarii.
To find how many coins are not denarii, subtract the number of denarii from the total number of silver coins.
DCCXC = 790 and CCCXXV = 325.
790 - 325 = 465.
465 in Roman numerals is CDLXV.
Therefore, CDLXV coins are not denarii.
If a historian writes a book divided into DCCXC chapters and each chapter takes III weeks to research, how many weeks in total does the research take?
The total research takes MMCCLXX weeks.
Multiply the number of chapters by the number of weeks per chapter.
DCCXC = 790 chapters and III = 3 weeks.
790 × 3 = 2370.
2370 in Roman numerals is MMCCLXX.
Therefore, the research takes MMCCLXX weeks.
Write the Roman Numeral for the difference between 1580 and DCCXC using the subtraction method.
The Roman numeral for the difference is DCCXC.
First, find the difference between the numbers.
1580 - 790 = 790.
790 in Roman numerals is DCCXC.
Therefore, the Roman numeral for the difference is DCCXC.
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.