Rules of Roman Numeration

We will learn about Roman Numeration and its rules. We know that there are seven basic Roman Numerals. They are I, V, X, L, C, D and M. These numerals stand for the number 1, 5, 10, 50, 100, 500 and 1000 respectively. We already learned about the numerals I, V, X, L and C and now we will learn about the remaining two numerals.

There is another symbol ‘─’ which is called bar. If bar is place over a numeral, it is multiplied by 1000. Thus, V and XII stand for 5000 and 12000 respectively.

Rules of Roman Numeration:

$Rules of Roman Numerals$

1. First Rule: Numerals of the same value are added.

When the same symbol is repeated, the value of the symbol is added to get the value of the numeral. I, X and C can be repeated only up to three times. Symbols V, L and D are never repeated.

For example:

I I I stands for 1 + 1 + 1 = 3

XX = 10 + 10 = 20

X X X stands for 10 + 10 + 10 = 30

CC = 100 + 100 = 200

C C C stands for 100 + 100 + 100 = 300

M M M stands for 1000 + 1000 + 1000 = 3000

Note:

(i) Symbols V, L and D are not repeated.

(ii) A symbol cannot be repeated more than three times.

2. Second Rule: A symbol of smaller value put on the right of greater value symbol is added to it.

The values of the symbols are added or subtracted to find the values of the Roman numerals. When the smaller numeral is written to the right of a greater numeral, the value of the smaller numeral is added to the greater numeral.

For example:

VI stands for 5 + 1 = 6

CV = 100 + 5 = 105

CX = 100 + 10 = 110

CXX stands for 100 + 10 + 10 = 120

DC = 500 + 100 = 600

MC = 1000 + 100 = 1100

MCL stands for 1000 + 100 + 50 = 1150

3. Third Rule. A symbol of smaller value put on the left of greater value symbol is subtracted from it.

When the smaller numeral is written to the left of a greater numeral, the value of the smaller numeral is subtracted from the greater numeral. The V, L and D are not subtracted. Only one number can be subtracted from another.

For example:

IV stands for 5 - 1 = 4

IX stands for 10 - 1 = 9

XL stands for 50 - 10 = 40

XC stands for 100 - 10 = 90

DC stands for 500 - 100 = 400

Note:

(i) Symbol V, L and D are never subtracted.

(ii) Symbol I can be subtracted from V and X only.

(iii) Symbol X can be subtracted from L and C only as L and C are greater than X.

(iv) Symbol C can be subtracted from D and M.

4. Fourth Rule. A symbol of smaller value, put between two symbols of greater value is subtracted from the symbol on its right.

When the symbols are combined to make a numeral, the value of the symbol between the two symbols is subtracted from the value of the symbol on its right.

For example:

XIV stands for 10 + 5 - 1 = 14

LIX stands for 50 + 10 - 1 = 59

XCIX stands for 90 + 10 - 1 = 99

XLIX stands for 40 + 10 - 1 = 49

You might like these

Roman Numerals | System of Numbers | Symbol of Roman Numerals |Numbers
How to read and write roman numerals? Hundreds of year ago, the Romans had a system of numbers which had only seven symbols. Each symbol had a different value and there was no symbol for 0. The symbol of Roman Numerals and their values are: Romans used different
Worksheet on Operations on Roman Numerals | Word Problems | Answers
In worksheet on Operations on Roman Numerals we will solve various types of practice questions on Addition on Roman Numerals; subtraction of Roman Numerals; multiplication of Roman Numerals; division of Roman Numerals and some word problems on Roman Numerals. Here you will
4th Grade Roman Numerals Worksheet | Grade 4 Roman Numerals
Practice the questions given in the 4th Grade Roman Numerals Worksheet. The questions are based on Roman numerals, Hindu-Arabic numerals and rules to write Roman numerals. I. Write the Roman numerals for each of the following Hindu – Arabic numerals:
Worksheet on Roman Symbols |Rules to write Roman Numbers |Hindu-Arabic
Practice the questions given in the worksheet on Roman symbols. The questions are based on Roman symbols and rules to write Roman numbers. I. Express as Hindu-Arabic numerals: (i) IV (ii) IX (iii) XIV (iv) XIX (v) VI (vi) XXXI (vii) III (viii) XIII (ix) VIII (x) XXIX
Worksheet on Roman Numerals |Roman Numerals|Symbols for Roman Numerals
Practice the worksheet on roman numerals or numbers. This sheet will encourage the students to practice about the symbols for roman numerals and their values. Write the number for the following: (a) VII (b) IX (c) XI (d) XIV (e) XIX (f) XXVII (g) XXIX (h) XII
Roman Symbols | What are Roman Numbers? | Roman Numeration System
Do we know from where Roman symbols came? In Rome, people wanted to use their own symbols to express various numbers. These symbols, used by Romans, are known as Roman symbols, Romans used only seven symbols V, X, L, C, D, M to express different numbers.
Operations on Roman Numerals |Add |Subtraction|Multiplication|Division
The four basic operations on Roman numerals are addition; subtraction; multiplication and division. The Roman numerals satisfy the commutative, associative and distributive laws for addition, subtraction, multiplication and division.If we add, subtract, multiply or div
Worksheet on Comparison of Roman Numerals | Hindu - Arabic Numerals
Practice the worksheet on comparison of roman numerals. In worksheet on comparison of roman numerals we will solve various types of practice questions on roman numerals. Here you will get 20 different types of questions on comparison of roman numerals. Compare the given