Chapter 11

Dallying with Decimals

In This Chapter

arrow Understanding the decimal basics

arrow Applying decimals to the Big Four operations

arrow Looking at decimal and fraction conversions

arrow Making sense of repeating decimals

Because early humans used their fingers for counting, the number system is based on the number 10. So numbers come in ones, tens, hundreds, thousands, and so on. A decimal — with its handy decimal point — allows people to work with numbers smaller than 1: tenths, hundredths, thousandths, and the like.

Here's some lovely news: Decimals are much easier to work with than fractions (which I discuss in Chapters 9 and 10). Decimals look and feel more like whole numbers than fractions do, so when you're working with decimals, you don't have to worry about reducing and increasing terms, improper fractions, mixed numbers, and a lot of other stuff.

Performing the Big Four operations — addition, subtraction, multiplication, and division — on decimals is very close to performing them on whole numbers (which I cover in Part II of the book). The numerals 0 through 9 work just like they usually ...

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