Lesson 1 – Roman Numerals: I, V, X

  • Objective: Review and practise Roman numerals: I, V, X

Introductory Video

Introduction

Today, we’re going to learn about Roman numerals. These are a way of writing numbers that was used by the ancient Romans, and we still use them sometimes today. Roman numerals look different from the numbers we usually use. Instead of digits like 1, 2, or 3, Roman numerals use letters. The three most important Roman numerals to start with are I, V, and X. Let’s explore what these letters mean and how to use them!

Roman Numerals: I, V, and X

  1. I = 1
    The numeral I represents the number 1. Every time you see I, it means one.
  2. V = 5
    The numeral V stands for the number 5. It’s used to show five things or five items.
  3. X = 10
    The numeral X means 10. So, when you see X, think of ten things.

How Roman Numerals Work

Roman numerals are a little different from our normal numbers because you can add or subtract values depending on how the letters are arranged. Let’s learn how it works!

Adding Roman Numerals

When a smaller numeral is placed after a bigger numeral, you add the numbers.

  • VI = 5 + 1 = 6
    Here, V is 5 and I is 1, so we add them together to get 6.
  • XII = 10 + 1 + 1 = 12
    In this case, X is 10, and there are two I‘s (each worth 1). So, 10 + 1 + 1 gives us 12.

Subtracting Roman Numerals

When a smaller numeral is placed before a bigger numeral, you subtract the smaller number from the bigger one.

  • IV = 5 – 1 = 4
    Here, I is 1 and V is 5, but because the I comes first, you subtract 1 from 5, which gives you 4.
  • IX = 10 – 1 = 9
    In this example, I is 1 and X is 10, so when the smaller number comes first, you subtract 1 from 10 to get 9.

Using Roman Numerals

You can use I, V, and X to write lots of numbers. Here are a few more examples:

  • III = 1 + 1 + 1 = 3
    (Three I’s together mean 3.)
  • VIII = 5 + 1 + 1 + 1 = 8
    (V means 5, and three I’s add up to 3 more, making 8.)
  • XV = 10 + 5 = 15
    (X is 10, and V is 5, so you add them to get 15.)

Why Roman Numerals are Important

You might see Roman numerals used in different places, like:

  • Clocks with Roman numerals instead of regular numbers.
  • Books or movies with Roman numerals to show the volume or sequel number (like Volume III for the third book).
  • In sports events, like the Super Bowl, where they use Roman numerals to show the number of the event.

Conclusion

Now you know the basics of Roman numerals! You learned that I stands for 1, V stands for 5, and X stands for 10. By adding or subtracting these numerals, you can create different numbers. Roman numerals may look a little different, but with practice, they become easy to understand. Try writing your age or your favourite number in Roman numerals to practice!