CHAPTER 2 - INTRODUCTION TO WHOLE NUMBERS

Whole numbers are the numbers we use for counting. They start from 0 and go on forever: 0, 1, 2, 3, 4, 5, and so on.

Whole numbers do not include fractions, decimals, or negative numbers.

Some examples of whole numbers:

And the pattern continues: 10, 11, 12, ... up to infinity.

We can represent whole numbers on a number line. Let's look at the numbers from 0 to 10:

The number line helps us visualize the order of numbers and the distance between them.

Whole numbers have some special properties:

• They start from 0 and go to infinity
• Every whole number has a successor (next number)
• Every whole number except 0 has a predecessor (previous number)
• They can be used for counting and ordering
• Addition and multiplication of whole numbers always result in whole numbers

Our number system is based on groups of ten. Each digit in a number has a place value.

For example, in the number 345:

• 5 is in the ones place
• 4 is in the tens place (4 × 10 = 40)
• 3 is in the hundreds place (3 × 100 = 300)

So, 345 = 300 + 40 + 5

Addition combines two or more numbers to find their total.

Example: 7 + 5 = 12

When we add whole numbers, the result is always a whole number.

Subtraction finds the difference between two numbers.

Example: 9 - 4 = 5

When subtracting whole numbers, the result may not always be a whole number if we subtract a larger number from a smaller one.

Multiplication is repeated addition.

Example: 4 × 3 = 4 + 4 + 4 = 12

When we multiply whole numbers, the result is always a whole number.

Division splits a number into equal parts.

Example: 12 ÷ 3 = 4

When dividing whole numbers, the result may not always be a whole number.

We use whole numbers every day in many situations:

• Counting: How many students are in class? How many books do you have?
• Measuring: How many centimeters long is your pencil?
• Time: How many hours of sleep did you get last night?
• Money: How many rupees do you have in your pocket?
• Sports: What's the score in the game?

In this chapter, you will learn:

• How to identify and write whole numbers
• How to represent whole numbers on a number line
• The place value system for whole numbers
• How to compare and order whole numbers
• Basic operations with whole numbers
• How to solve word problems using whole numbers