What You Will Learn
- Identify whole numbers.
- Understand the role of zero in the set of whole numbers.
- Compare and order whole numbers.
- Add, subtract, multiply and divide whole numbers.
- Apply whole-number skills to everyday problems.
What Are Whole Numbers?
Whole numbers are numbers that do not contain fractions or decimal parts. They begin with zero and continue without end in the positive direction.
There is no largest whole number because you can always add 1 to a whole number to produce another whole number.
Whole Numbers and Zero
Zero is an important part of the whole-number system. It represents the absence of a quantity and is included in the set of whole numbers.
If there are no books on a table, the number of books can be represented by 0.
Negative numbers such as −1 and −5 are not whole numbers. Fractions such as 1/2 and decimals such as 2.5 are also not whole numbers.
Comparing Whole Numbers
We can compare whole numbers using the symbols >, < and =.
On a number line, a number farther to the right is greater than a number farther to the left.
Ordering Whole Numbers
To order whole numbers from smallest to largest, begin with the number closest to zero and move upward.
Order these numbers from smallest to largest:
Answer: 0, 3, 9, 14, 21
Adding Whole Numbers
Addition combines two or more quantities to find their total.
We can also separate the numbers into tens and ones:
Subtracting Whole Numbers
Subtraction finds the difference between quantities or tells us how much remains after taking one quantity away.
Always line up place values correctly when using the column method.
Multiplying Whole Numbers
Multiplication can be understood as repeated addition.
4 groups of 3 make 12.
7 groups of 5 make 35.
Dividing Whole Numbers
Division separates a quantity into equal groups or finds how many times one number fits into another.
This means 24 can be divided into 6 equal groups, with 4 in each group.
Common Mistakes
−3 is not a whole number.
1/2 is not a whole number.
0 is a whole number.
Quick Practice
Try these questions before checking your answers.
Which of these is a whole number: 3.5, −2, 0 or 1/4?
Arrange 7, 2, 15, 0 and 9 from smallest to largest.
Calculate: 36 + 24.
Calculate: 75 − 28.
Calculate: 8 × 7.
Summary
- Whole numbers start at 0 and continue upward.
- Negative numbers, fractions and decimals are not whole numbers.
- Whole numbers can be compared and ordered.
- The four basic operations can be performed with whole numbers.
- Practice helps develop accuracy and confidence.