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Last updated on February 24th, 2025

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686 in Roman Numerals

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Intermediate
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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.

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What is 686 in Roman Numerals?

Royal titles such as Henry I, Henry II, and so on often use Roman Numerals. Have you noticed these symbols (I and II) and wondered what they represent? Those are Roman Numerals.

 

In ancient times, people used fingers, sticks, bones, etc., to count. As life became complex, a standard system was required for counting. The Ancient Romans developed the Roman Numeral system for this purpose. In this system, the symbols I (1), V (5), X (10), L (50), C (100), D (500), and M (1000) are used.

 

In Roman Numerals, we use DCLXXXVI to represent 686. Here, D is 500, C is 100, L is 50, X is 10, and VI is 6. Let’s learn more about Roman numerals and how we write them.686 in roman numerals

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Basic Rules for 686 in Roman Numerals

There are certain basic rules for writing numbers 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, DCLXXXVI → D + C + L + X + X + V + I → 500 + 100 + 50 + 10 + 10 + 5 + 1 = 686.

 

Rule 2: Repetition Method

 

To write larger numbers, certain Roman Numerals can be repeated up to three times. For example, XXX → 30.

 

Rule 3: Subtraction Method

 

If a small number precedes a larger 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

 

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 VVV for 15; instead, we use XV.

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How to Write 686 in Roman Numerals

Let’s now learn how to write 686 in Roman Numerals. Follow these methods to write the number in Roman Numerals:

 

  • By Expansion Method
  • By Grouping Method
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686 in Roman Numerals by Expansion Method

In the expansion method, the number is broken down based on its place value. In this section, we will learn how to write 686 in Roman numerals using the expansion method. To write 686 in Roman Numerals, follow the steps:

 

Step 1: Break the number based on place value: hundreds, tens, and ones. For 686, we write it as 600 + 80 + 6.

 

Step 2: Convert the numbers into Roman Numerals:
 

  • 600 in Roman Numerals - DC (500 + 100)
     
  • 80 in Roman Numerals - LXXX (50 + 10 + 10 + 10)
     
  • 6 in Roman Numerals - VI (5 + 1)

 

Step 3: Combine the Roman Numerals together. Therefore, 686 in Roman Numerals is DC (600) + LXXX (80) + VI (6) = DCLXXXVI.

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686 in Roman Numerals by Grouping Method

When writing a large number in Roman Numerals, we group the number. To write 686 in Roman Numerals, we group 686 as 600 + 80 + 6.

 

  • 600 in Roman Numerals - DC
     
  • 80 in Roman Numerals - LXXX
     
  • 6 in Roman Numerals - VI

 

So, 686 is written as DCLXXXVI in Roman Numerals.

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Common Mistakes and How to Avoid Them in 686 Roman Numerals

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686 in Roman Numerals Examples

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Problem 1

A historian discovers a manuscript mentioning a battle involving CDLXXX soldiers on one side and CCVI on the other. What is the total number of soldiers involved in the battle?

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Explanation

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Problem 2

A library has a collection of DCCXL books, and the librarian decides to distribute these books equally into IV sections. How many books will each section contain?

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Explanation

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Problem 3

An ancient inscription states that a journey took CCCLXXXIV days, which was CCLXXXII days shorter than another journey. How long was the longer journey?

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Explanation

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Problem 4

A merchant records a profit of DCCCXLII denarii after expenses of CLVI denarii. What was the total income?

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Explanation

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Problem 5

Write the Roman Numeral for 600 + 86 using the expansion method.

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Explanation

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FAQs on 686 in Roman Numerals

1.What is 600 in Roman numerals?

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2.How to write 686 in Roman numerals?

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3.What is 700 in Roman Numerals?

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4.Is DCLXXXVI a prime number?

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5.What are the multiples of 686?

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Important Glossaries for 686 in Roman Numerals

  • Addition rule: The addition method is used when a larger numeral is followed by a smaller numeral, and the values are added. For example, DCLXXXVI = 500 + 100 + 50 + 10 + 10 + 5 + 1 = 686.
     
  • Grouping method: Here, the given numbers are grouped based on their place value and then converted into Roman numerals. For example, 686 = 600 + 80 + 6 = DCLXXXVI.
     
  • Repetition rule: Certain symbols (I, X, C, M) in the Roman numeric system can be repeated only up to three times. For example, XXX = 30 (X is repeated three times to represent the number 30).
     
  • Expansion method: This method involves breaking down the number according to its place value and converting each group into Roman Numerals. For example, 686 = 600 + 80 + 6 = DCLXXXVI.
     
  • Subtraction rule: A smaller numeral placed before a larger numeral means the smaller is subtracted from the larger. For example, IV = 5 - 1 = 4.
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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.

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Fun Fact

: She loves to read number jokes and games.

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