Whole Numbers

 

Natural Numbers

All the positive counting numbers starting from one are called Natural Numbers.

Predecessor and Successor

If we add 1 to any natural number, we get the next number, which is called the Successor of that number.

12 + 1 = 13

So 13 is the successor of 12.

If we subtract 1 from any natural number, we get the predecessor of that number.

12 – 1 = 11

So 11 is the predecessor of 12.

Remark: There is no predecessor of 1 in natural numbers.

Whole Numbers

Whole numbers are the collection of natural numbers including zero. So, the zero is the predecessor of 1 in the whole numbers.

Number Line

To draw a number line, follow these steps-

(i) Draw a line and mark a point 0 on it.

(ii) Now mark the second point to the right of zero and label it as 1.

(iii) The distance between the 0 and 1 is called the unit distance.

(iv) Now you can mark other points as 2, 3, 4 and so on with the unit distance.

This is the number line for the whole numbers.

1. The distance between two points

The distance between 3 and 5 is 2 units. Likewise, the distance between 1 and 6 is 5 units.

2. The greater number on the number line

The number on the right is always greater than the number on the left.

As number 5 is on the right of the number 2, Hence 5>2.

3. A smaller number on the number line

The number on the left of any number is always smaller than that number.

As number 3 is on the left of 7, so 3 < 7.

Addition on the Number Line

If we have to add 7 and 5, then start with 7 and make 5 jumps to the right. As our 5th jump is at 12 so the answer is 12.

The sum of 7 and 5 is 7 + 5 = 12

Subtraction on the Number Line

If we have to subtract 3 from 7, then we have to start from 7 and make 3 jumps to the left. As our 3rd jump is at 4, so the answer is 4.

The subtraction of 6 from 10 is 10 – 6 = 4.

Multiplication on the Number Line

If we have to multiply 4 and 3, then Start from 0, make 4 jumps using 3 units at a time to the right, as you reach to 12. So, we say, 3 × 4 = 12.