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Whole Numbers

Suppose you have a bag full of candies. Now, suppose you want to count the number of candies in the bag. How will you start counting?

You will start counting as 1, 2, 3, 4, 5 and so on.

Therefore, we can say that the above numbers are counting numbers and are known as natural numbers.

Now, consider the natural number 5. Can you tell which number is the predecessor of 5 and which number is the successor of 5?

The predecessor of 5 is 4 and the successor of 5 is 6.

How? Let us first define these terms.

Successor

 “If 1 is added to any natural number, then we obtain the successor of that number.”

For example, the successor of 11 will be 11 + 1 = 12.

Predecessor

 “If 1 is subtracted from any natural number, then we obtain the predecessor of that number.”

For example, the predecessor of 11 will be 11 − 1 = 10.

To understand this better take a look at the given video.

Note:

(1) Every natural number has a successor because there is no largest natural number.

(2) Successor and predecessor are reverse of each other.

For example, 20 is the successor of 19 and 19 is the predecessor of 20.

(3) Every number except 1 has a predecessor in case of natural numbers. This is because 1 − 1 = 0 and 0 is not a natural number. It is a whole number.

Let us now see a few examples to understand the concept better.

Example 1:

Write two successors and two predecessors of 245600.

Solution:

First Successor = 245600 + 1 = 245601

Second Successor = 245601 + 1 = 245602

First Predecessor = 245600 − 1 = 245599

Second Predecessor = 245599 − 1 = 245598

Example 2:

Write the number right before and after 893.

Solution:

Number before 893 = 893 − 1 = 892

Number after 893 = 893 + 1 = 894

Example 3:

Write four numbers next to 91.

Solution:

This means that we have to find four successors of 91.

Successor of 91 = 91 + 1 = 92

Successor of 92 = 92 + 1 = 93

Successor of 93 = 93 + 1 = 94

Successor of 94 = 94 + 1 = 95

Thus, four numbers next to 91 are 92, 93, 94, and 95.

We know what whole numbers are. These numbers can be represented on a line, which is called the number line. We can use this number line to determine whether a number is greater or lesser than another given number. Let us take the help of this video to understanâ€¦

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