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Roman Numerals

In earlier times, there were many numeral systems Remember
like the Indian, Chinese, Arabic, etc. Some of them
are still in use like the Hindu-Arabic numeral system The Roman numeral
system does not have a
which uses the numerals 0, 1, 2, 3, 4, 5, 6, 7, 8 and symbol for zero.
9. Another such system of numeration is the Roman
numeral system.

The Roman numeral system, developed by the Romans thousands of years ago, is
based on seven letters of the alphabet. All the numbers are written using either one
of the letters or combinations of letters.

Symbols

The seven letters used in the Roman numeral system and their corresponding values
in Hindu-Arabic numeral system are given in the following table.

Symbol I V X L C D M

Value 1 5 10 50 100 500 1000

In this class we will learn only about the first three symbols, i.e., I, V and X.

Reading Roman Numerals

We have seen that there are symbols for numbers 1, 5, 10, 50, 100, 500 and 1000. To

make the rest of the numbers of the Hindu-Arabic numeral system, we either add the
numbers or subtract them according to the rules given below.

Rule 1: When a symbol is repeated, it means the value Remember
of each symbol is added. The sum is equal to the
number formed. But, any symbol cannot be repeated Roman numeral V cannot
more than 3 times. be repeated at all.

For example, II = 1 + 1 = 2, 111 = 1 + 1 + 1 = 3,

XX = 10 + 10 = 20, XXX = 10 + 10 + 10 = 30

Rule 2: When a smaller symbol or symbols are written after a larger one, then their
values are added to get the number.

For example, VI = 5 + 1 = 6, XV = 10 + 5 = 15, VII = 5 + 1 + 1 = 7, VIII = 5 + 1 + 1 + 1 = 8,
XIII = 10 + 1 + 1 + 1 = 13

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