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5.1: Introduction to Decimals

  • Page ID
    114907
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    A gas station sign is shown. It lists unleaded as 3.999, mid-grade as 4.099, and premium as 4.199.
    Figure 5.1 The price of a gallon of gasoline is written as a decimal number. (credit: Mark Turnauckus, Flickr)

    Chapter Outline

    5.1 Decimals
    5.2 Decimal Operations
    5.3 Decimals and Fractions
    5.4 Solve Equations with Decimals
    5.5 Averages and Probability
    5.6 Ratios and Rate
    5.7 Simplify and Use Square Roots

    Gasoline price changes all the time. They might go down for a period of time, but then they usually rise again. One thing that stays the same is that the price is not usually a whole number. Instead, it is shown using a decimal point to describe the cost in dollars and cents. We use decimal numbers all the time, especially when dealing with money. In this chapter, we will explore decimal numbers and how to perform operations using them.


    This page titled 5.1: Introduction to Decimals is shared under a CC BY 4.0 license and was authored, remixed, and/or curated by OpenStax.

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