One use for decimals is in working with percents, which are commonplace in everyday life:
There are
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$\,100\,$ cents in a dollar.
A century is
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$\,100\,$ years.
The word percent means per one hundred .
The symbol $\%$ is used for percent.
Whenever you see the symbol
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$\%$ , you can trade it in
for a factor of $\,\frac{1}{100}\,$.
Whenever you see a factor of
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$\,\frac{1}{100}\,$,
it can be traded in for a $\%$ symbol.
This simple idea is the key to success with percents:
Indeed, the symbol $\%$ even looks a bit like the fraction $\,\frac{1}{100}\,$;
it has the two zeros and the division bar!
To change from a decimal to a percent,
move the decimal point two places to the right and insert the percent symbol.
Here's the idea that makes this work:
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$\displaystyle 0.03 = \frac{3}{100} = 3\cdot\frac{1}{100} = 3\%$
Notice that the $\displaystyle\,\frac{1}{100}\,$ gets traded in for the percent symbol.
Here, you will practice renaming decimals as percents.
For example, $\,0.54\,$ gets renamed as $\,54\%\,$.