Roman Number System
Roman number system: We have been using the Hindu-Arabic numeral system so far. This is not the only system available. One of the early systems of writing numerals is the system of Roman number system. This system is still used in many places. |
1 | I | 14 | XIV | 27 | XXVII | 150 | CL |
2 | II | 15 | XV | 28 | XXVIII | 200 | CC |
3 | III | 16 | XVI | 29 | XXIX | 300 | CCC |
4 | IV | 17 | XVII | 30 | $\chi \chi\chi$ | 400 | CD |
5 | V | 18 | XVIII | 31 | $\chi \chi\chi$1 | 500 | D |
6 | VI | 19 | XIX | 40 | XL | 600 | DC |
7 | VII | 20 | XX | 50 | L | 700 | DCC |
8 | VIII | 21 | XX1 | 60 | LX | 800 | DCCC |
9 | IX | 22 | XXII | 70 | LXX | 900 | CM |
10 | X | 23 | XXIII | 80 | L$\chi \chi\chi$ | 1000 | M |
11 | XI | 24 | XXIV | 90 | XC | 1600 | MDC |
12 | XII | 25 | XXV | 100 | C | 1700 | MDCC |
13 | XIII | 26 | XXVI | 101 | CI | 1900 | MCM |
Unlike the Hindu-Arabic Numeral System, Roman Numeral System uses 7 basic symbols to represent different numbers. The symbols are as follows :
I = 1 V =5 X= 10
L = 50 C =100 D=500
M= 1000
Rules to form Roman Numerals :
1) If symbol is repeated then its value is added.
2)The symbols I,X,C and M can be repeated maximum 3 times.
3)The symbols V,L and D can never be repeated.
4)If a symbol with smaller value is written on right of greater value then smaller value is added to the greater one.
5)If a symbol with smaller value is written on left of greater value then smaller value is subtracted from the greater one.
Example : 1) Write equivalent Roman numerals of a) 29 b) 395 c)62
Solution : a) 29---> XXIX
b)395 ---> CCCXCV
c) 62 ---> LXII
Example: 2) Write a) XLIV b)DCC in Hindu-Arabic numerals.
Solution : a)XLIV ----> 44
b)DCC ----> 700
Example : 3) Add XXII + CD
Solution :
XXII = 22
CD = 400
XXII + CD = 22 +400
= 422
Example : 4)Add XLIV + LIV
Solution :
XLIV = 44
LIV = 54
∴ XLIV + LIV = 44 + 54
= 98
98 = XCVIII
Example : 5) Subtract DCC - L$\chi \chi\chi$V
Solution :
DCC = 700
L$\chi \chi\chi$V = 85
∴DCC - L$\chi \chi\chi$V = 700 - 84
= 616
616 = DCXVI
Number System
• Roman number system
• International System of Numeration
• Rounding Numbers