Converting
Fractions Decimals and Percentages
Unit Objective
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Converting between
fractions, decimals, and percentages
Percents as Fractions
Words
A percent is the value of a part-to-whole ratio
where the whole is 100. So, you can write a percent as a fraction with a
denominator of 100. The symbol % is used to denote a percent.
Numbers
Algebra
n% = 
Writing Percents as
Fractions
a) Write 35% as a fraction in simplest
form.
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b) Write 35% as a fraction in simplest
form.
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c) Write 174% as a mixed number in simplest form.
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Let's practice.
Convert
the following to a fraction.
1) 5%
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2)168%
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3) 36%
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4) 83%
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Fractions as Decimals
To convert fractions to decimals we divide the numerator(top) by
the denominator(bottom).
Convert to decimal: 
7 ÷ 15 = 
=
0.47 (Rounded to 100th.)
Divide 3 by 5 = 0.6,
then put the 1 in front = 1.6
Let's practice.
Convert
the following fractions to decimals. Round to the nearest 100th if necessary.
1)
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2)
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3)
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Decimals to Percent
Moving
the decimal point 2 place to the right will change a decimal to a percent.
(This is the same as multiplying by 100) and add the percent symbol.
Examples:
0.65
= 65%
1.38
= 138%
0.07
= 7%
0.0045
= 0.45%
0.8
= 80%
Modeling in Real Life
A store is having a sale, offering a 20% discount on all
items. If an item originally costs $50, how much will it cost during the sale?
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To solve this problem change 20% to a decimal and then
multiply by 50.
50 × 0.20 = 10
Therefore, 10 dollars off of the price. 50 – 10 = 40
So, it will cost $40.