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.
Rules of Roman Numeration:
1. Numerals of the same value are added.
I I I stands for 1 + 1 + 1 = 3
X X X stands for 10 + 10 + 10 = 30
C C C stands for 100 + 100 + 100 = 300
M M M stands for 1000 + 1000 + 1000 = 3000
(i) Symbols V, L and D are not repeated.
(ii) A symbol cannot be repeated more than three times.
2. A symbol of smaller value put on the right of greater value symbol is added to it.
VI stands for 5 + 1 = 6
CXX stands for 100 + 10 + 10 = 120
MCL stands for 1000 + 100 + 50 = 1150
3. A symbol of smaller value put on the left of greater value symbol is subtracted from it.
IV stands for 5 - 1 = 4
IX stands for 10 - 1 = 9
XL stands for 50 - 10 = 40
(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. A symbol of smaller value, put between two symbols of greater value is subtracted from the symbol on its right.
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`