Page 12 - ICSE Math 5

Indian and International Number Systems

We have learnt about Indian number system up to lakhs period and International number system
up to millions period. Let’s revise and extend these number systems to study large number up to
9-digit.

Indian Number System

According to the Indian number system, we divide a large number into groups where each group
represents a period. Each period consists of place values.
The first period includes ones, tens and hundreds, and is called the ones or units period. The
second period includes thousands and ten thousands, and is called the thousands period.
The third period includes lakhs and ten lakhs, and is called the lakhs period. The fourth period
includes crores and ten crores, and is called the crores period.
The purpose of writing large numbers in periods is to make it easier to know the place values of
different digits in the given number and compare it with the other numbers.

The given place value chart includes crores in the Indian number system.

PERIODS CRORES LAKHS THOUSANDS ONES
Place Ten Crores Ten Lakhs Ten Thousands Hundreds Tens Ones
Values Crores Lakhs Thousands
(TC) (C) (TL) (L) (TTh) (Th) (H) (T) (O)
To read and write a large number such as 438546213 as per the Indian number system, we put
commas to separate the periods of ones, thousands, lakhs and crores.

Top Tip
43,85,46,213
Ones Start from the extreme
right of a 9-digit number
Thousands and put commas after the
Periods 3 , 5 and 7 digits as you
th
th
rd
Lakhs move left to separate it
Crores into periods.

The above given number, 43,85,46,213 is read as forty-three crore eighty-five lakh forty-six
thousand two hundred thirteen.
Example 1: Separate 923540295 into periods as per the Indian number system by putting
commas. Also, make the place value chart and write the number name.
Solution: The given number can be written as 92,35,40,295.

PERIODS CRORES LAKHS THOUSANDS ONES

Place Ten Crores Ten Lakhs Ten Thousands Hundreds Tens Ones
Values Crores Lakhs Thousands

(TC) (C) (TL) (L) (TTh) (Th) (H) (T) (O)
923540295 9 2 3 5 4 0 2 9 5
So, 92,35,40,295 is written as ninety-two crore thirty-five lakh forty thousand two hundred
ninety-five.

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