Math 015 Section 8.1 Percents

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Math 015 Section 8.1 Percents
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Obj To write a percent as a fraction or a
decimal
Percent means parts of 100
In the figure at the right, 23 of the 100 squares
are shaded.
We say that 23 of the squares are shaded.
In most application problems it will be necessary
to convert percents to fractions or decimals in
order to work with them in the problems.
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Obj To write a percent as a fraction or a
decimal
To write a percent as a fraction
1. remove the percent sign
2. divide by 100
3. simplify the fraction
Examples change the following percents to
fractions
13
13 100
13


100
44
11 25

44

100
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Obj To write a percent as a fraction or a
decimal
To write a percent as a fraction
1. remove the percent sign
2. divide by 100
3. simplify the fraction
Examples change the following percents to
fractions
25
240
12
240



2
100
5
1
23
16
1 100
23
50
16

16



3
100
2
5
Certain percents and their fraction equivalents
should be memorized
1 5
20 25 50 75

1 6
23
16 33 66

1 4
1 3
13
1 2
2 3
23
3 4
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Obj To write a percent as a fraction or a
decimal
To write a percent as a decimal
1. remove the percent sign
2. divide by 100
Examples change the following percents to
decimals
61

61

100

0.61

0.5
0.5

100

0.005

235
235

100

2.35
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Obj To write a fraction or a decimal as a
percent
To write a fraction or decimal as a percent
1. multiply by 100
Examples change the following to percents
38
100
38
300
75
12



37




8
2


0.048
0.048
100

4.8

1.17
100
1.17


117
8
Obj To write a fraction or a decimal as a
percent
To write a fraction or decimal as a percent
1. multiply by 100
Write as a percent write the remainder in
fraction form
56
100
56
500
250
13




83



6
3
Write as a percent round to the nearest tenth
100
13
1300
49



144.4


1
9
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