Roman Numerals

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Reading Roman Numerals

Roman numerals are the numbers used by people in Roman times.

Roman numerals

In maths we tend to use 0, 1, 2, 3, 4, 5, 6, 7, 8 and 9 to write numbers.
The Romans used letters to show different numbers.
- E.g. the number 2 is shown as two 1s (II).
- E.g. the number 6 is shown as one 5 and one 1 (VI).

Rules of Roman numerals

No single letter can be repeated more than 3 times.
If the digit to the right is a smaller number, you add it to the digit on the left:
- VI $\rightarrow$ 5 and 1 $\rightarrow$ 5 + 1 = 6
If the digit to the left is a smaller number, you subtract it from the digit on the right:
- IV $\rightarrow$ 1 and 5 $\rightarrow$ 5 − 1 = 4

Zero

The Romans did not have the idea of zero in their counting.
That means there is no zero in Roman numerals.
Roman numerals don't have place values like we use in maths.

Writing Roman Numerals up to 100

We can use our rules to write Roman numerals with amounts up to 100.

Multiples of 10.

Certain multiples of 10 have special characters in Roman numerals.
- E.g. the number 30 is written as three tens, XXX.
- E.g. the number 55 is written as one fifty and one ten, LV.

Making up numbers

To write a large number in Roman numerals, write the tens first and then the ones.
Then we add them together.
E.g. the number 76 is written as:
- 70 is written as one five and two tens, LXX.
- 6 is written as one five and one one, VI.
76 is LXXVI in Roman numerals.

Rules

To make numbers up to 100, we need to add another rule.
A small letter to the left of a big letter has to be at least one-tenth of the big letter.
- For example, for 99 we don't write IC.
- I is equal to 1, which is less than one-tenth of 100 (10).
- That means 99 is XCIX in Roman numerals.

1Year 3 - Number

2Year 3 - Measurement

2.1Length

2.1.1Length

2.1.2Comparing Lengths

2.1.3Add & Subtract Lengths

2.1.4Perimeter

2.2Mass

2.2.1Mass

2.2.2Comparing Masses

2.2.3Add & Subtract Masses

2.3Volume & Capacity

2.3.1Volume & Capacity

2.3.2Comparing Volumes

2.3.3Add & Subtract Volumes

2.4Money

2.4.1Money

2.4.2Counting Money

2.4.3Adding & Subtracting Money

2.5Time

2.5.1Units of Time

2.5.2Clocks

2.5.3Telling the Time

2.5.4Time of the Day

2.5.512-Hour & 24-Hour Clocks

2.5.6Measuring Time

3Year 3 - Geometry

3.1Angles

3.1.1Angles in Degrees

3.1.2Types of Angle

3.2Properties of Shapes

3.2.12D Shapes

3.2.23D Shapes

3.3Straight Lines

3.3.1Straight Lines

3.3.2Parallel & Perpendicular Lines

4Year 3 - Statistics

4.1Statistics

4.1.1Statistics

4.1.2Pictograms & Bar Charts

5Year 4 - Number

6Year 4 - Measurement

6.1Units

6.1.1Metric Measurements

6.1.2Adding & Subtracting Money

6.2Time

6.2.1Converting Units of Time

6.2.2Changing the 12-Hour Clock to the 24-Hour Clock

6.2.3Changing the 24-hour Clock to the 12-Hour Clock

7Year 4 - Geometry

7.1Properties of Shapes

7.1.1Symmetry

7.1.2Types of Triangle

7.1.3Quadrilaterals

7.2Perimeter & Area

7.2.1Perimeter

7.2.2Area

7.3Position & Direction

7.3.1Coordinates

7.3.2Translation

8Year 4 - Statistics

8.1Statistics

8.1.1Types of Data

8.1.2Pictograms & Bar Charts

8.1.3Line Graphs

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