﻿ Changing Percents to Decimals
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 $\,\%\,$ symbol is replaced with a factor of $\,\frac{1}{100}\,$:

EXAMPLES:
$3.5\% = 3.5\cdot\frac{1}{100} = \frac{3.5}{100} = 0.035$

$25\% = 25\cdot \frac{1}{100} = \frac{25}{100} = 0.25$

$50\% = 50\cdot \frac{1}{100} = \frac{50}{100} = 0.5$

$100\% = 100\cdot \frac{1}{100} = \frac{100}{100} = 1$

$250\% = 250\cdot \frac{1}{100} = \frac{250}{100} = 2.5$

As these examples illustrate, the percent symbol instructs multiplication by $\,\frac{1}{100}\,$ (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:
$3\% = 0.03$

$2.37\% = 0.0237$

$0.01\% = 0.0001$

$5032\% = 50.32$

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
For example, $\,54\%\,$ gets renamed as $\,0.54\,$.