Page 5 - Maths Class 06

Numbers – Our Friends

Introduction

By now we have learnt how to deal with small as well as large numbers and Indian and International
place value system of numbers. We have also done addition, subtraction, multiplication and division of

numbers in our previous classes. We have also seen patterns in numbers and some sequences, etc. In this
lesson, we will move further and learn how to handle large numbers. We will also learn about the
conversion of length from one unit to another and relation between different units, comparison of
numbers, estimation of numbers and Roman Numerals.

Number System

Place Value and Face Value

The place value of a digit of a number depends upon its position in the number. The face value of a digit of
a number does not depend upon its position in the number. It always remains the same wherever it lies
regardless of the place it occupies in the number.

Example : Let us see the place value and face value of the highlighted digit in the number 1,32,460.
The digit 2 in the number 1,32,460 lies in the thousands period (1000) and hence the place value of 2 is
2 thousands (or 2000). The face value of 2 is 2 only.
Expanded Form

When a number is written as the sum of the place NOTE

values of all the digits of the number, then the number Place value of 0 is always 0.
is in its expanded form.

For example : The expanded form of 9,67,480 is as shown below:
9,67,480 = 900000 + 60000 + 7000 + 400 + 80 + 0.

Indian System of Numeration
In this system, only ten symbols namely, 0, 1, 2, 3, 4, 5, 6, 7, 8 and 9 are used to write various numerals
representing whole numbers.

So, it is called base 10 system or decimal system. In a numeral, going from right to left, the value of each
place is ten times the value of the place to its next as shown:

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