# Changing Decimals to Percents

Need some basic practice with decimals first? Changing Decimals to Fractions and Multiplying and Dividing Decimals by Powers of Ten

One use for decimals is in working with *percents*,
which are commonplace in everyday life:

- the dress was on sale for $\,40\%\,$ off the original price;
- housing costs rose $\,5\%\,$ last year;
- there was a $\,150\%\,$ increase in telephone activity after the newspaper advertisement.

There are
$\,100\,$ **cent**s in a dollar.
A **cent**ury is
$\,100\,$ years.
The word *percent* means *per one hundred* .

The symbol $\%$ is used for percent. Whenever you see the symbol $\%$ , you can trade it in for a factor of $\,\frac{1}{100}\,.$ Whenever you see a factor of $\,\frac{1}{100}\,,$ 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.

## Examples

$2.5 = 250\%$

$1.008 = 100.8\%$

Here's the idea that makes this work:

Notice that the $\displaystyle\,\frac{1}{100}\,$ gets traded in for the percent symbol.

## Practice

Here, you will practice renaming decimals as percents. For example, $\,0.54\,$ gets renamed as $\,54\%\,.$