copyright©amberpasillas2010 changing fractions to percents and changing decimals to percents for...
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Changing Fractions To Percents
and
Changing Decimals to Percents
For today’s lesson get a calculator!
TAKE OUT A CALCULATOR
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Percent means “per hundred.”
100of
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“Cent” comes from Latin and means 100.
Many words have come from the root word cent such as centimeter (100 cm), century (100 years), ¢ipede (100 legs).
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The letter C in Roman Numerals stands for 100 or “cent”.
CCC means 300.
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We use percents with money. The dollar is in hundredths.
If you understandmoney then
learning percents will be
easy!
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$ .50 is ½ of a dollar 50% also means ½
50¢
50¢
=$1.00
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20% .2020100
15= = =
Decimal
FractionFractionSimplifie
dPercent
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50% = 50 parts out of 100 or 50 hundredths.1 2 3 4 5 6 7 8 9 10
11 12 13 14 15 16 17 18 19 20
21 22 23 24 25 26 27 28 29 30
31 32 33 34 35 36 37 38 39 40
41 42 43 44 45 46 47 48 49 50
51 52 53 54 55 56 57 58 59 60
61 62 63 64 65 66 67 68 69 70
71 72 73 74 75 76 77 78 79 80
81 82 83 84 85 86 87 88 89 90
91 92 93 94 95 96 97 98 99 100
50100
12
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10% = 10 parts out of 100 or 10 hundredths.1 2 3 4 5 6 7 8 9 10
11 12 13 14 15 16 17 18 19 20
21 22 23 24 25 26 27 28 29 30
31 32 33 34 35 36 37 38 39 40
41 42 43 44 45 46 47 48 49 50
51 52 53 54 55 56 57 58 59 60
61 62 63 64 65 66 67 68 69 70
71 72 73 74 75 76 77 78 79 80
81 82 83 84 85 86 87 88 89 90
91 92 93 94 95 96 97 98 99 100
10100
110
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How many hundredths are red?
How many hundredths are yellow?
Say it as a DECIMAL and then as a PERCENT!
32 hundredths = 0.32WHICH EQUAL 32%
68 hundredths = 0.68WHICH EQUALS 68%
Notice that 32% + 68% = 100%
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0.4 = 0.40
What percent is green?
40% green
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What percent is green?
0.4 = 0.40
You do NOT need the zero!
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Name The Percent
42% 33% 75%
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To change a Fraction to a Percent: Set up an equivalent fraction using a denominator of 100.
35 = 60%
2020
60
25
25
Per-cent means per 1001 ?
4 100
25=
100= 25%
100
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To change a Fraction to a Percent: Set up an equivalent fraction using a denominator of 100.
1) 37
5074=
100
= 74%
22
2) 18200
9=100
= 9%
22
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To change a Fraction to a Percent: Set up an equivalent fraction using a denominator of 100.
3) 93
30031=
100
= 31%
33
4) 3645
4=5
80=100
= 80%
99 20
20
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To Change a Decimal to a Percent: Multiply the decimal by 100.0.85 • 100 = 85%
* Multiplying by 100 results in moving the decimal 2 places to the right.
0.85
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Change The Decimals To Percents
DECIMALS
ANSWER
DECIMALS
ANSWER
1) 0.50 2) 0.3
3) 0.82 4) 0.115
5) 1.56 6) 0.001
50% 30%
82% 11.5%
156% 0.1%
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To Change a Fraction to a Percent
25
5)2.00.4
2 000
0
000
Change it to a decimal first. Divide the numerator by the denominatorChange your decimal to a percent. Multiply your decimal by 100. This is the same as moving the decimal 2 places to the right.
0.40 = 40%
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Change The Fractions To Percents
FRACTIONS
ANSWER
FRACTIONS
ANSWER
12.5% 66.6%
30%250%
40%
1
81)
3)
5)
2)
6)
3
102
5
2
35
23
4
4)
75%
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REMEMBER: To Always Show Your Work
Take out your study guide!!!
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#9
To change a Fraction to a Percent: Set up an equivalent fraction using a denominator of 100.
25%
35
2020
14
2525
?100
60100
60%
Per-cent means per 100