# Irrational Numbers

Videos and lessons to help Grade 8 students know that numbers that are not rational are called irrational. Understand informally that every number has a decimal expansion; for rational numbers show that the decimal expansion repeats eventually, and convert a decimal expansion which repeats eventually into a rational number.

Common Core: 8.NS.1

### Suggested Learning Targets

• I can define rational and irrational numbers.
• I can show that the decimal expansion of rational numbers repeats eventually.
• I can convert a decimal expansion which repeats eventually into a rational number
• I can show informally that every number has a decimal expansion

Related Topics:

Common Core for Mathematics

More Math Lessons for Grade 8

Understand and apply the definition of rational numbers - 8.NS.1
In this lesson, you will learn how to use and apply the definition of the term Rational Number.

Understand and apply the definition of irrational numbers - 8.NS.1
In this lesson, you will learn the definition of an irrational number and apply the definition to recognize irrational numbers.

Distinguish between rational and irrational numbers - 8.NS.1
In this lesson, you will learn to differentiate between rational numbers and irrational numbers.

8NS1 Rational and Irrational Numbers
Know that there are numbers that are not rational, and approximate them by rational numbers.

Ordering Rational Numbers

Compare irrational and rational numbers - 8.NS.1
In this lesson, you will learn to compare an irrational number to a rational number or to another irrational number.

Convert repeating decimals into fractions - 8.NS.1
In this lesson, you will learn to convert repeating decimals into fractions, thus proving that they are rational numbers.

Rational and Irrational Numbers.

8.NS.1 Decimals to Fractions.

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