Roman Numerals

In mathematics, Roman numerals are a numeral system that originated in ancient Rome and remained the usual way of writing numbers throughout Europe well into the Late Middle Ages.

In this article, we will discuss the Roman numerals.

Basics

Roman numbers a numeric system that originated in ancient Rome. Unlike the Arabic numeral system (1, 2, 3, etc.), Roman numerals use letters of the alphabet to represent numbers. Here’s a quick reference to the most commonly used Roman numerals:

I – 1

V – 5

X – 10

L – 50

C – 100

D – 500

M – 1000

Examples of Roman Numerals to Arabic Numerals

III is 3 (I + I + I)

VII is 7 (V + I + I)

XV is 15 (X + V)

XCII is 92 (XC + II)

MMXXI is 2021 (M + M + X + X + I)

Table of 50 Roman Numerals

Roman Numeral	Arabic Numeral
I	1
II	2
III	3
IV	4
V	5
VI	6
VII	7
VIII	8
IX	9
X	10
XI	11
XII	12
XIII	13
XIV	14
XV	15
XVI	16
XVII	17
XVIII	18
XIX	19
XX	20
XXI	21
XXII	22
XXIII	23
XXIV	24
XXV	25
XXVI	26
XXVII	27
XXVIII	28
XXIX	29
XXX	30
XXXI	31
XXXII	32
XXXIII	33
XXXIV	34
XXXV	35
XXXVI	36
XXXVII	37
XXXVIII	38
XXXIX	39
XL	40
XLI	41
XLII	42
XLIII	43
XLIV	44
XLV	45
XLVI	46
XLVII	47
XLVIII	48
XLIX	49
L	50

Advanced Concepts

Roman Numerals in Mathematics

Roman numerals can be used for basic arithmetic operations. However, they are not as practical as Arabic numerals for complex calculations. Here’s an example of addition:

• XVII + IX = XXVI

Subtractive Principle

Roman numerals also employ the subtractive principle, which allows for more efficient representation. For instance:

IV represents 4 (one less than 5).

XC represents 90 (ten less than 100).