CHANGING PERCENTS TO DECIMALS

Whenever computations need to be done with percents, the percents are first renamed as decimals.

Here are examples of changing percents to decimals.
Notice that the [beautiful math coming... please be patient] $\,\%\,$ symbol is replaced with a factor of [beautiful math coming... please be patient] $\,\frac{1}{100}\,$:

EXAMPLES:
[beautiful math coming... please be patient] $3.5\% = 3.5\cdot\frac{1}{100} = \frac{3.5}{100} = 0.035$

[beautiful math coming... please be patient] $25\% = 25\cdot \frac{1}{100} = \frac{25}{100} = 0.25$

[beautiful math coming... please be patient] $50\% = 50\cdot \frac{1}{100} = \frac{50}{100} = 0.5$

[beautiful math coming... please be patient] $100\% = 100\cdot \frac{1}{100} = \frac{100}{100} = 1$

[beautiful math coming... please be patient] $250\% = 250\cdot \frac{1}{100} = \frac{250}{100} = 2.5$

As these examples illustrate, the percent symbol instructs multiplication by [beautiful math coming... please be patient] $\,\frac{1}{100}\,$ (or, equivalently, division by $\,100\,$),
which is accomplished by moving the decimal point two places to the left.
Remember that if you don't see a decimal point, then it gets inserted just to the right of the ones place.

Now, you can go from percents to decimals in one easy step,
by moving the decimal point two places to the left:

EXAMPLES:
[beautiful math coming... please be patient] $3\% = 0.03$

[beautiful math coming... please be patient] $2.37\% = 0.0237$

[beautiful math coming... please be patient] $0.01\% = 0.0001$

[beautiful math coming... please be patient] $5032\% = 50.32$

Some of my students find this memory device helpful:
PuDdLe   DiPpeR   (Imagine a little kid, barefoot, dipping piggy-toes in puddles!)
Percent to Decimal, two places to the Left
Decimal to Percent, two places to the Right

Master the ideas from this section
by practicing the exercise at the bottom of this page.

When you're done practicing, move on to:
Introduction to Sets

 
 

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

Change to a decimal:
    
(an even number, please)