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Chapter1 6 ½ –

Knowing Our Numbers

Numbers have become an inseparable part of To find greater number among given numbers,
our lives and whether we work in our daily we can identify them easily by simply counting
routine, each one of us uses numbers as a part the digits in the numbers. The numbers
of our everyday life. Numbers are endless. having more digits are greater than numbers
We have discussed numbers in earlier classes. having less digits. If number of digits are same
We use numbers in many ways. We compare then, look at this example:
them, arrange them in increasing and To compare 51845 and 41964 that which is
decreasing orders. We have already studied greater? This is also easy, as the digit in ten
basic operations:– addition, subtraction, thousands place is 5 in 51845 and 4 in 41964.
multiplication and division of big numbers too. So 51845 > 41964.
Before learning more about numbers, it is time Now try to say which is greater, 58672 or
to look back at what we have already learnt. 57875? As 5 is in ten thousands place in both
The smallest 6-digit number is 1,00,000 (One numbers, we compare the next place i.e.
Lakh). The largest 6-digit number is 9,99,999 thousands. As 8 > 7. So 58672 is bigger i.e.
(Nine Lakh Ninety-Nine Thousand Nine 58672 > 57875.
Hundred Ninety-Nine). If the digits in the thousands place is also the
Lets have a number 687542. same, what will we do? Move to the hundreds
To make it easy to read, we put commas in it as place to compare and then tens place and
6,87,542 and read it as Six Lakh Eighty-Seven finally units place.
Thousand Five Hundred Forty-Two.

Indian system of numeration
Values of the places in the Indian system of numeration are Ones, Tens, Hundreds, Thousands,
Ten thousands, Lakhs, Ten Lakhs, Crores and so on.
The following place value chart can be used to identify the digit’s value in any place in the Indian
system.

Periods Crores Lakhs Thousands Ones
Places Tens Ones Tens Ones Tens Ones Hundreds Tens Ones

International system of numeration

Values of the places in the International system of numeration are Ones, Tens, Hundreds,
Thousands, Ten thousands, Hundred thousands, Millions, Ten millions and so on.
1 million = 1000 thousands,
1 billion = 1000 millions
Below given place-value chart can be used to identify the digit’s, value in any place in the
International system.

Periods Billions Millions Thousands Ones

Places Hundreds Tens Ones Hundreds Tens Ones Hundreds Tens Ones Hundreds Tens Ones

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Mathematics In Focus - 6