687 in Roman Numerals

Royal titles, such as Henry I, Henry II, and so on, use Roman numerals. Have you noticed these and wondered what the symbols (I, II) represented? Those are Roman numerals. In earlier times, people counted using fingers, sticks, bones, etc. As life became complex, a standard form was required.

Ancient Romans used the Roman numeral system, employing symbols like I (1), V (5), X (10), L (50), C (100), D (500), and M (1000). In Roman numerals, 687 is represented as DCLXXXVII. Here, D is 500, C is 100, L is 50, X is 10, and VII is 7.

Let’s learn more about Roman numerals and how we write them.

Certain basic rules exist for writing numbers in Roman numerals. Let’s discuss some rules to remember when writing numbers in Roman numerals.

Rule 1: Addition Method

The addition method is used when a smaller number is placed after a larger number. For example, DCLXXXVII → D (500) + C (100) + L (50) + X (10) + X (10) + V (5) + I (1) + I (1) = 687

Rule 2: Repetition Method

Certain Roman numerals can be repeated up to three times. For instance, XXX → 30 (X repeated three times represents 30).

Rule 3: Subtraction Method

When a smaller number precedes a larger one, it is subtracted. 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 VV for 10; instead, we use X.

Let’s learn how to write 687 in Roman numerals through different methods:

• By Expansion Method
• By Grouping Method

The expansion method breaks down a number based on place value. This section explains how to write 687 in Roman numerals using the expansion method. To write 687 in Roman numerals, follow these steps:

Step 1: Break down the number based on place value (ones, tens, hundreds, etc.). For 687, it’s 500 + 100 + 50 + 10 + 10 + 5 + 1 + 1

Step 2: Convert each number into Roman numerals:

• 500 in Roman numerals - D
   
• 100 in Roman numerals - C
   
• 50 in Roman numerals - L
   
• 10 in Roman numerals - X
   
• 5 in Roman numerals - V
   
• 1 in Roman numerals - I

Step 3: Combine the Roman numerals together. Therefore, 687 in Roman numerals is D (500) + C (100) + L (50) + X (10) + X (10) + V (5) + I (1) + I (1) = DCLXXXVII

When writing a larger number in Roman numerals, we group it. To write 687 in Roman numerals, group 687 as 500 + 100 + 50 + 10 + 10 + 5 + 1 + 1

• 500 in Roman numerals - D
   
• 100 in Roman numerals - C
   
• 50 in Roman numerals - L
   
• 10 in Roman numerals - X
   
• 5 in Roman numerals - V
   
• 1 in Roman numerals - I

So, 687 is written as DCLXXXVII in Roman numerals.

Roman numerals follow a certain pattern. Here are numbers related to 687 in Roman numerals:

• Addition Method: When a large number is followed by a smaller numeral, their values are added. For example, DCLXXXVII = D + C + L + X + X + V + I + I = 687
   
• Expansion Method: Breaking down a number into its place values and converting each into Roman numerals. For example, 687 = 500 + 100 + 50 + 10 + 10 + 5 + 1 + 1 = DCLXXXVII
   
• Repetition Rule: In Roman numerals, certain symbols (I, X, C, M) can be repeated up to three times. For example, XXX = 30
   
• Subtraction Method: When a smaller numeral precedes a larger numeral, subtract the smaller from the larger. For example, IX = X - I = 9
   
• Grouping Method: Grouping numbers based on their place value before converting to Roman numerals. For example, 687 = 500 + 100 + 50 + 10 + 10 + 5 + 1 + 1 = DCLXXXVII