Math 9 Numeracy – Unit 4.5
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Percent Conversions
4.5 - Percent Conversions
What is a percent? Percent means “out of each hundred” and has the symbol %. Percents are used
for all sorts of things, but most commonly in things like sales tax, interest at a bank, discounts in a
store or commissions in a wage.
Percents can be expressed in any one of three ways;
When you use percents in an equation, you must convert the percent (%) into either a fraction
or as a decimal. It is often easiest and most common to use the decimal form.
To change a percent to a decimal, simply move the decimal point two decimal places to the left and
drop the percent sign (%)
Your turn…
Directions: Convert the following percents into decimals.
In order to convert back from decimals to a percent, simply move the decimal point two places to
the right and add a percent sign (%)
Directions: Convert from decimals to percents. The first one has been done for you.
Remember you place values. The second place value to the right of the decimal point is the
“hundredths”. This means that any decimal can be written as a number over 100. For example;
Directions: Convert from decimals to fractions out of 100, like the example above.
Directions: Convert from fractions out of 100 to decimals. The first one has been done for you.
If you are asked to convert a fraction that is NOT out of a hundred into a decimal or a percent you
solve as a ratio equation.
Your turn…
Directions: Convert the following fractions into percents, by first converting them into fractions
out of one hundred, like the example above.