Learn to relate decimals, fractions, and percents'

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Learn to relate decimals, fractions, and
percents.
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Vocabulary
percent
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Percents are ratios that compare a number to 100.
30
50
75
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(No Transcript)
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To convert a fraction to a decimal, divide the
numerator by the denominator.
To convert a decimal to a percent, multiply by
100 and insert the percent symbol.
0.125 ? 100 ? 12.5
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Additional Example 1 Finding Equivalent Ratios
and Percents
Find the missing ratio or percent equivalent for
each letter ag on the number line.
a
10
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Additional Example 1 Finding Equivalent Ratios
and Percents
Find the missing ratio or percent equivalent for
each letter ag on the number line.
b
0.25
25
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Additional Example 1 Finding Equivalent Ratios
and Percents
Find the missing ratio or percent equivalent for
each letter ag on the number line.
c
40
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Additional Example 1 Finding Equivalent Ratios
and Percents
Find the missing ratio or percent equivalent for
each letter ag on the number line.
d
0.60
60
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Additional Example 1 Finding Equivalent Ratios
and Percents
Find the missing ratio or percent equivalent for
each letter ag on the number line.
e
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Additional Example 1 Finding Equivalent Ratios
and Percents
Find the missing ratio or percent equivalent for
each letter ag on the number line.
0.875
f
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Additional Example 1 Finding Equivalent Ratios
and Percents
Find the missing ratio or percent equivalent for
each letter ag on the number line.
g
125
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Try This Example 1
Find the missing ratio or percent equivalent for
each letter ag on the number line.
e
c
50
12
g
25
75
1
a
b
d
f
0.125
a
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Try This Example 1 Continued
Find the missing ratio or percent equivalent for
each letter ag on the number line.
e
c
50
12
g
25
75
1
a
b
d
f
b
25
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Try This Example 1 Continued
Find the missing ratio or percent equivalent for
each letter ag on the number line.
e
c
50
12
g
25
75
1
a
b
d
f
c
0.375
37
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Try This Example 1 Continued
Find the missing ratio or percent equivalent for
each letter ag on the number line.
e
c
50
12
g
25
75
1
a
b
d
f
d
50
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Try This Example 1 Continued
Find the missing ratio or percent equivalent for
each letter ag on the number line.
e
c
50
12
g
25
75
1
a
b
d
f
e
0.625
62
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Try This Example 1 Continued
Find the missing ratio or percent equivalent for
each letter ag on the number line.
e
c
50
12
g
25
75
1
a
b
d
f
f
75
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Try This Example 1 Continued
Find the missing ratio or percent equivalent for
each letter ag on the number line.
e
c
50
12
g
25
75
1
a
b
d
f
100

g
1
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Additional Example 2 Finding Equivalent
Fractions, Decimals, and Percents
Find the equivalent fraction, decimal, or percent
for each value given on the circle graph.
0.15(100) 15
0.12(100) 12
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Additional Example 2 Continued
You can use information in each column to make
three equivalent circle graphs. One shows the
breakdown by fractions, one shows the breakdown
by decimals, and one shows the breakdown by
percents.
The sum of the fractions should be 1.
The sum of the decimals should be 1.
The sum of the percents should be 100.
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Try This Example 2
Fill in the missing pieces on the chart below.
0.1(100) 10
0.45
0.25
0.25(100) 25
0.2
0.2(100) 20
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Additional Example 3 Physical Science Application
Gold that is 24 karat is 100 pure gold. Gold
that is 14 karat is 14 parts pure gold and 10
parts another metal, such as copper, zinc,
silver, or nickel. What percent of 14 karat gold
is pure gold?
Set up a ratio and reduce.
7 ? 12
Find the percent.
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Try This Example 3
A bakers dozen is 13. When a shopper purchases
a dozen items at the bakery they get 12. It is
said that the baker eats 1 item from every batch.
So, what percentage of the food the baker cooks
is eaten without being sold?
Set up a ratio and reduce.
1 ? 13
0.077
Find the percent.
7.7
So the baker, eats 7.7 of the items they bake.
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Lesson Quiz
Find each equivalent value. 1. as a percent 2.
20 as a fraction 3. as a decimal 4. as
a percent 5. About 342,000 km2 of Greenlands
total area (2,175,000 km2) is not covered with
ice. To the nearest percent, what percent of
Greenlands total area is not covered with ice?
37.5
0.625
56
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