BrightChamps Logo
Hamburger Menu Icon for BrightChamps Website Navigation

Math Table of Contents Dropdown Table Of Contents

Creative Math Ideas Image
Live Math Learners Count Icon117 Learners

Last updated on February 25th, 2025

Math Whiteboard Illustration

900 in Roman Numerals

Professor Greenline Explaining Math Concepts
Foundation
Intermediate
Advance Topics

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 more. Here we will be discussing Roman Numerals, rules, and examples.

Professor Greenline from BrightChamps

What is 900 in Roman Numerals?

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. As life became more 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 CM to represent 900, where C is 100 and M is 1000. Let's learn more about Roman numerals and how we write them.900 in roman numerals

Professor Greenline from BrightChamps

Basic Rules for 900 in Roman Numerals

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, VI → V + I → 5 + 1 = 6

 

Rule 2: Repetition Method

 

To write a large number, there are certain Roman Numerals that can be repeated three times. III → 3.

 

Rule 3: Subtraction Method

 

If a small number is placed before a large number in Roman Numerals, we subtract the smaller number from the large number. This is the subtraction method. For example, CM → M - C → 1000 - 100 = 900

 

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 DDD for 1500; instead, we use MD for 1500.

Professor Greenline from BrightChamps

How to Write 900 in Roman Numerals

Let’s now learn how to write 900 in Roman Numerals. Follow these methods to write the number in Roman Numerals.

 

  • By Expansion Method
  • By Grouping Method
Professor Greenline from BrightChamps

900 in Roman Numeral by Expansion Method

In the expansion method, based on the place value, the number is broken down. In this section, we will learn how to write 900 in Roman numerals using the expansion method. To write 900 in Roman Numerals, follow the steps:

 

Step 1: The number is broken based on the place value, such as ones, tens, hundreds, etc. For 900, we write it as 1000 - 100

 

Step 2: Converting the number into Roman Numerals

  • 1000 in Roman Numeral - M
     
  • 100 in Roman Numeral - C

 

Step 3: Applying the subtraction method. Therefore, 900 in Roman Numeral is M (1000) - C (100) = CM

Professor Greenline from BrightChamps

900 in Roman Numeral by Grouping Method

When writing a large number into Roman Numerals, we group the number. To write 900 in Roman Numeral, we group it as 1000 - 100

 

  • 1000 in Roman Numeral — M
     
  • 100 in Roman Numeral — C

 

So, 900 is written as CM in Roman Numerals.

Max Pointing Out Common Math Mistakes

Common Mistakes and How to Avoid Them in 900 Roman Numerals

Max from BrightChamps Saying "Hey"

900 in Roman Numerals Examples

Ray, the Character from BrightChamps Explaining Math Concepts
Max, the Girl Character from BrightChamps

Problem 1

A historian is cataloging CM ancient coins, each representing a year. How many centuries do these coins represent?

Ray, the Boy Character from BrightChamps Saying "Let’s Begin"

Explanation

Max from BrightChamps Praising Clear Math Explanations
Max, the Girl Character from BrightChamps

Problem 2

An archaeologist finds a chest containing CM ancient scrolls and wants to share it equally among XLV museums. How many scrolls does each museum receive?

Ray, the Boy Character from BrightChamps Saying "Let’s Begin"

Explanation

Max from BrightChamps Praising Clear Math Explanations
Max, the Girl Character from BrightChamps

Problem 3

A mathematician is calculating the sum of DCC and CC. What is the result in Roman numerals?

Ray, the Boy Character from BrightChamps Saying "Let’s Begin"

Explanation

Max from BrightChamps Praising Clear Math Explanations
Max, the Girl Character from BrightChamps

Problem 4

A philosopher has collected a library of CM books and wishes to donate CCC books. How many books will remain?

Ray, the Boy Character from BrightChamps Saying "Let’s Begin"

Explanation

Max from BrightChamps Praising Clear Math Explanations
Max, the Girl Character from BrightChamps

Problem 5

Convert the number 900 using the Roman numeral expansion method.

Ray, the Boy Character from BrightChamps Saying "Let’s Begin"

Explanation

Max from BrightChamps Praising Clear Math Explanations
Ray Thinking Deeply About Math Problems

FAQs on 900 in Roman Numerals

1.What is 800 in Roman numerals?

Math FAQ Answers Dropdown Arrow

2.How to write 900 in Roman numerals?

Math FAQ Answers Dropdown Arrow

3.What is 1000 in Roman Numerals?

Math FAQ Answers Dropdown Arrow

4.Is CM a prime number?

Math FAQ Answers Dropdown Arrow

5.What are the multiples of 900?

Math FAQ Answers Dropdown Arrow
Professor Greenline from BrightChamps

Important Glossaries for 900 in Roman Numerals

  • Subtraction rule: This method is used when a smaller numeral precedes a larger numeral, indicating subtraction. For example, CM = 1000 - 100 = 900.
     
  • Addition rule: The addition method is used when a larger numeral is followed by a smaller one, indicating addition. For example, VI = 5 + 1 = 6.
     
  • Grouping method: Here, numbers are grouped based on their place value, and then each group is converted into its Roman numerals. For example, 900 = 1000 - 100 = CM.
     
  • Repetition rule: Certain symbols (I, X, C, M) in the Roman numeric system can be repeated only up to three times. For example, III = 3 (I is repeated three times to represent the number 3).
     
  • Limitation rule: Some symbols like V, L, and D cannot be repeated in the Roman numeral system.
Math Teacher Background Image
Math Teacher Image

Hiralee Lalitkumar Makwana

About the Author

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.

Math Teacher Fun Facts Image
Max, the Girl Character from BrightChamps

Fun Fact

: She loves to read number jokes and games.

BrightChamps Logo
Follow Us
BrightChamps Facebook Page IconBrightChamps YouTube Channel IconBrightChamps Instagram IconBrightChamps LinkedIn Page Icon
INDONESIA
Axa Tower 45th floor, JL prof. Dr Satrio Kav. 18, Kel. Karet Kuningan, Kec. Setiabudi, Kota Adm. Jakarta Selatan, Prov. DKI Jakarta
INDIA
H.No. 8-2-699/1, SyNo. 346, Rd No. 12, Banjara Hills, Hyderabad, Telangana - 500034
SINGAPORE
60 Paya Lebar Road #05-16, Paya Lebar Square, Singapore (409051)
USA
251, Little Falls Drive, Wilmington, Delaware 19808
VIETNAM (Office 1)
Hung Vuong Building, 670 Ba Thang Hai, ward 14, district 10, Ho Chi Minh City
VIETNAM (Office 2)
143 Nguyễn Thị Thập, Khu đô thị Him Lam, Quận 7, Thành phố Hồ Chí Minh 700000, Vietnam
Dubai
BrightChamps, 8W building 5th Floor, DAFZ, Dubai, United Arab Emirates
UK
Ground floor, Redwood House, Brotherswood Court, Almondsbury Business Park, Bristol, BS32 4QW, United Kingdom