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Common Core MathK - 8
High School

Grade 8: The Number System
660 questions6 skills

8.NS.A.1

630 questions5 skills

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.

Converting 1-digit repeating decimals to fractions

Converting decimals to fractions 2

Converting multi-digit repeating decimals to fractions

Recognizing rational and irrational numbers

Writing fractions as repeating decimals

8.NS.A.2

30 questions1 skill

Use rational approximations of irrational numbers to compare the size of irrational numbers, locate them approximately on a number line diagram, and estimate the value of expressions (e.g., π²).

Approximating irrational numbers