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Hindu - Arabic number system

Many years ago, Hindus and Arabs developed a number system called the
Hindu - Arabic number system.
It is the name given to the number system that we use today.

Roman Numerals
It is the numeral system that originated in ancient Rome. This numeral system

is based on certain letters, which are given values and are as used as numerals.
The following are the seven number symbols used in the Roman numeral
system and their values.

Symbols I V X L C D M

Value 1 5 10 50 100 500 1000

Seven letters of English alphabet, i.e. I, V, X, L, C, D and M, are used to

represent Roman numerals. Roman numerals do not have a symbol for zero.
Roman numerals are read from left to right, and are arranged from the largest
to the smallest. Multiplication, division and other complex operations were

difficult to perform on Roman numerals. So Hindu - Arabic numerals were used.

The Roman numerals for the numbers 1 - 15 are shown below :

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

I II III IV V VI VII VIII IX X XI XII XIII XIV XV

The Roman numerals are used in some cases.

Rules for Roman numerals :

8 In Roman numerals, a symbol is not repeated more than thrice. If a symbol is
repeated, its value is added as many times as it occurs. For example, if the
letter I is repeated thrice, then its value is three.

For example : III = 1 + 1+ 1 = 3, XXX = 10 + 10 + 10 = 30

CCC = 100 + 100 +100 = 300, MMM = 1000 + 1000 + 1000 = 3000
8 The symbols V, L and D are never repeated.
8 If a symbol of smaller value is written to the right of a symbol of greater value,

then its value gets added to the symbol of greater value. For example, in case
of VI, I is written to the right of V. It means that 1 should be added to 5. Hence,

its value is 6.
8 If a symbol of smaller value is written to the left of a symbol of greater value,
then its value is subtracted from the symbol of greater value. For example, in

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Mathematics In Focus - 5