# Roman numerals

Long before the **Arabs** introduced their numbering system to Europe and this continent traveled to America and the rest of the world, thousands of years ago, in what was known as **Ancient Rome** , the Romans invented a **numbering system** the which we still use in many of the things. This numbering system is what we currently know by the name of **Roman numerals** .

## What are Roman numerals?

Roman numerals are a **non-positional** numbering system in which **simple ****ideograms** consisting of seven **capital letters are used,** each of which is represented by a **numerical value** .

- Definition
- Characteristics of Roman numerals
- Source
- History
- Who invented them
- What are they for
- Rules
- Operations with Roman numerals
- Importance
- Roman numerals from 1 to 50
- Roman numerals from 51 to 100
- Examples
- Curiosities

## Definition

Roman numerals are those that are considered as a **non- ****positional ****numbering system** in which the numbers are represented by means of simple **ideograms** consisting of seven **capital letters** , each of which corresponds to a **numerical value** .

## Characteristics of Roman numerals

The main characteristics of Roman numerals are the following:

- Roman numerals are made up of a series of
**letters**that are: I = 1, V = 5, X = 10, L = 50, C = 100, D = 500, M = 1,000 - Each
**stripe**that is placed on**top**of the number means that the figure is multiplied by a thousand. - The order of placement of Roman numerals is always from
**highest**to**lowest**value so that thousands are placed first, then hundreds, tens and units. - In the writing of Roman numerals letters can never be
**repeated**more than three times in a row. - It is a
**non-positional**system in which values are assigned to certain letters.

## Source

Although we do not know exactly how the Roman numerals arose, we can say that they were most likely born from the **Etruscan ****numeral system** , although there **are** different **versions** that tell us about their adaptation by the **Romans** .

## History

Throughout the history of **the Roman Empire** , the number system, Roman numerals, was used, which was developed in ancient Rome and is still observed in some ancient buildings. This numbering system comes from **Etruscan** , since ancient writings of these peoples have been found that show that the Romans used the **symbols** of this culture to represent **quantities** , and later the Romans adapted them to their alphabet.

With the passage of time there are still references in which the use of this numerical system can be observed, although it is not a system that is used daily, but it can still be observed in some areas such as **books** , **clocks** and to mention **centuries** .

## Who invented them

Roman numerals were invented by the culture belonging to the **Etruscans** and then spread throughout **Rome** , **Europe,** and the rest of the **world** .

## What are they for

At present, Roman numerals have many different uses, among which we can mention the following:

**To name the centuries**: they are used to name the number of the century in which we are or in which a certain matter happened. For example: we are in the 21st century, the French Revolution happened in the 18th century, Michelangelo painted the Sistine Chapel in the 16th century.**To name the kings**: Roman numerals are used to designate the generation of kings or very important characters in history, for example: Fernando II of Aragon, Felipe IV , Pope John Paul II .**To number the volumes or parts of some books or films**: they are also currently used to name chapters or volumes of this type of activity, for example: The Godfather II, Chapter IV of a thesis.**For anniversaries, meetings or celebrations**that are held periodically

## Rules

There are different **rules** regarding the function, use and also writing of Roman numerals, these rules are:

- Roman numeral symbols are
**written**and must be**read**from**left**to**right**, from highest to lowest value. - In Roman numerals when a
**lower**value**symbol**is placed to the left of another, then it must be**subtracted**. - The 5 symbols and their multiples (V, L, D) will always
**add up**and cannot be placed to the left of a higher value one. - When writing Roman numerals, only a maximum of
**three**consecutive**repetitions**of the**same symbol**are allowed . - A symbol in Roman numerals that appears by
**subtracting**can only be repeated when its repetition is placed**more than one symbol**away to its right. - Only a
**type 1**symbol**(I, X, C, M)**can be**subtracted**from the immediate major of type 1 or type 5 (V, L, D). - The symbol
**I**can only be used to**subtract V and X.** - The symbol
**X**can only be used to**subtract L and C**. - The symbol
**C**can only**subtract D and M.**

## Operations with Roman numerals

To perform operations using Roman numerals, it is important to know that by itself, the system could not reach the number 4,000, so when it is necessary to represent a high number, a **horizontal line** is added above the **number** to indicate that this number is **multiplied. per thousand.**

To be able to make a **sum** of Roman numerals, the following **steps** must be followed :

**Subtractions**are converted into**additions****We link**the two numbers that we want to add.**We sort**the**symbols**in descending order depending on their value.- We do
**internal sums**from right to left. - We return to
**subtraction**in the places where it is necessary to respect the writing rules described above.

To perform **subtraction** of Roman numerals we do the following:

- Convert the
**subtractions**into**additions**. **Symbols common**to A and B must be eliminated- For the
**largest symbol**left in B we take the symbol of A greater than it and expand it. Then we apply step 2 again as many times as necessary. - We go back to
**subtraction**where necessary

To **multiply** Roman numerals is a bit more complicated and is usually multiplied and divided.

- It is
**divided**between 2 and write the**quotient**of the division under A. - Is
**multiplied**B by 2 and write the result under B. - Steps 1 and 2 are done again with the numbers that are obtained until a 1 appears in the left column.
- The resulting table is crossed out all the rows in which the number on the left is even.
- They will
**add**the**numbers**that have left us in the right column.

To **divide** there are no general rules and the **divisor** must be **subtracted from** the dividend until we reach a number less than the divisor. The number of times we have subtracted will be the quotient of the division.** **

## Importance

The importance of Roman numerals is that they were the first **numbering systems** that were used in ancient times to **add** and keep **accounts** , in addition, they are currently a mechanism to **number** some important items such as book chapters, centuries and are also used in watches.

## Roman numerals from 1 to 50

- I
- II
- III
- IV
- V
- SAW
- VII
- VIII
- IX
- X
- XI
- XII
- XIII
- XIV
- XV
- XVI
- XVII
- XVIII
- XIX
- XX
- XXI
- XXII
- XXIII
- XXIV
- XXV
- XXVI
- XXVII
- XXVIII
- XXIX
- XXX
- XXXI
- XXXII
- XXXIII
- XXXIV
- XXXV
- XXXVI
- XXXVII
- XXXVIII
- XXXIX
- XL
- XLI
- XLII
- XLIII
- XLIV
- XLV
- XLVI
- XLVII
- XLVIII
- XLIX
- L

## Roman numerals from 51 to 100

- L
- LI
- LII
- LIII
- LIV
- LV
- LVI
- LVII
- LVIII
- LIX
- LX
- LXI
- LXII
- LXIII
- LXIV
- LXV
- LXVI
- LXVII
- LXVIII
- LXIX
- LXX
- LXXI
- LXXII
- LXXIII
- LXXIV
- LXXV
- LXXVI
- LXXVII
- LXXVIII
- LXXIX
- LXXX
- LXXXI
- LXXXII
- LXXXIII
- LXXXIV
- LXXXV
- LXXXVI
- LXXXVII
- LXXXVIII
- LXXXIX
- XC
- XCI
- XCII
- XCIII
- XCIV
- XCV
- XCVI
- XCVII
- XCVIII
- XCIX
- C

## Examples

Some examples of Roman numerals are as follows:

- 8 is written
**VIII** - 36 is written
**XXXVI** - 752 is written
**DCCLII** - 2011 is written
**MMXI** - 49 is written
**IL** - 90 is written
**XC** - 99 is written
**IC** - 900 is written
**CM**

## Curiosities

Some curiosities of Roman numerals are the following:

- They differ from the great numbering of history, because Roman symbols are written and read from
**left**to**right**and are also always found from**highest**to**lowest**value. - Roman numerals can be read from
**1**and do not have or do not represent**0.**