Page 23 - Maths Class 06

Whole Numbers

Introduction

We all know, that Mathematics is incomplete without Arithmetic. Arithmetic means the mathematics of
numbers. In the same way, we can say that the knowledge of numbers is necessary for the study of
mathematics. There are many types of numbers. Here, we will study about natural numbers and whole
numbers.

Numerals
We know that, each and every collection can be associated with a number. We can associate number with
a single object, number with two objects and so on. Thus a number is a concept or an ideal. Different
civilization like Indo Arabic, Devnagri, Arab, Romans, etc. used different symbols to denote numbers. The
symbol which represents a number is called a numeral.
The numerals which are used in counting objects i e. ., … are called counting numbers or natural numbers.

Natural and Whole Numbers
In our day-to-day practice we use numbers for counting as well as calculating. To count the number of
children in our school, the number of notebooks in our bag, we count from 1, then go on to two, three,
four, and so on. The numbers used for counting 1, 2, 3.... are called counting numbers or natural
numbers.
We have seen that predecessor of any natural number can be found by subtracting 1 from the number
itself. But, what is the predecessor of 1?
As per the definition, predecessor of 1 is 1 1 0– = . NOTE

But 0 does not belong to natural numbers as 1 is the smallest
Every natural number is a whole
natural number. number but every whole number is not
Clearly, number 1 has no predecessor in natural numbers. a natural number as 0 is a whole
number but not a natural number.
The natural numbers along with zero, form the collection of
whole numbers.
Representation of Whole Numbers on the Number Line

Draw a straight line and mark any point, say 0 on it label it as O.
Mark points A, B, C, D, E, ..... to the right of 0 at equal intervals.
Label the point A as 1, the point B as 2, the point C as 3 ....... and so on. (Figure)

O A B C D E F G

0 1 2 3 4 5 6 7

Thus, we can represent every whole number on the number line.

23 Mathematics-6