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STANDARDS

Math

    Common Core Math

    Grade 8: The Number System

    8.NS.A

    Know that there are numbers that are not rational, and approximate them by rational numbers.

    8.NS.A.1

    Fully covered
    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.

    8.NS.A.2

    Fully covered
    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).