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Classifying numbers review

Review whole numbers, integers, rational, and irrational numbers.  Then, practice identifying each.  

Whole numbers

Whole numbers are numbers that do not need to be represented with a fraction or decimal. Also, whole numbers cannot be negative. In other words, whole numbers are the counting numbers and zero.
Examples of whole numbers:


Integers are whole numbers and their opposites. Therefore, integers can be negative.
Examples of integers:

Rational numbers

Rational numbers are numbers that can be expressed as a fraction of two integers.
Examples of rational numbers:

Irrational numbers

Irrational numbers are numbers that cannot be expressed as a fraction of two integers.
Examples of irrational numbers:

How are the types of number related?

The following diagram shows that all whole numbers are integers, and all integers are rational numbers. Numbers that are not rational are called irrational.
4 oval shapes representing different groups of numbers. Three of the oval shapes are embedded within one another. The oval shape labeled rational numbers contains the oval shape labeled integers, which contains the oval shape labeled whole numbers. The separate oval shape labeled Irrational numbers is to the right.
Want to learn more about classifying numbers? Check out this video.


Problem 1
What type of number is 5?
Choose all answers that apply:

Want to try more problems like this? Check out these exercises:
Classify numbers: rational & irrational
Classifying numbers

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