Warm Up

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Preview
Warm Up
California Standards
Lesson Presentation
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Warm Up Write each fraction in the simplest
form. 1. 2. 3. 4.
18 46
1 3
21 63
100 72
1 3
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(No Transcript)
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Vocabulary
terminating decimal repeating decimal
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In baseball, a players batting average compares
the number of hits with the number of times the
player has been at bat.
Hits At Bats
Player Hits At Bats Batting Average (thousandths)
Lance Berkman
Alex Rodriguez
172 544
172 544 0.316
544
172
172 601
172
601
172 601 0.286
To convert a fraction to a decimal, divide the
numerator by the denominator.
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Additional Example 1 Writing Fractions as
Decimals
Write each fraction as a decimal. Round to the
nearest hundredth, if necessary.
1 4
9 5
5 3
A.
B.
C.
1
.8
1
.6
6
6
0.2
5
9.0
5.000
5
3
4
8
3
5
20
20
40
20
18
40
20
0
0
18
9 5
5 3
1 4
1.8
1.67
0.25
20
18
2
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Check It Out! Example 1
Write each fraction as a decimal. Round to the
nearest hundredth, if necessary.
3 4
6 5
7 3
A.
B.
C.
1
.2
2
.3
3
3
0.7
5
6.0
7.000
5
3
4
2 8
6
5
20
10
10
20
9
10
10
0
0
9
6 5
7 3
3 4
1.2
2.33
0.75
10
9
1
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The decimals 0.75 and 1.2 are terminating
decimals because the decimals comes to an end.
The decimal 0.333 is a repeating decimal because
it includes a group of one or more digits (where
all digits are not zero) that repeats forever.
You can also write a repeating decimal with a bar
over the repeating part.
0.333 0.3 0.8333 0.83 0.727272
0.72
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Additional Example 2 Using Mental Math to Write
Fractions as Decimals
Write each fraction as a decimal.
4 5
A.
4 5
2 2
Multiply to get a power of ten in the denominator.


0.8
37 50
B.
Multiply to get a power of ten in the denominator.
37 50
2 2


0.74
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Check It Out! Example 2
Write each fraction as a decimal.
3 5
A.
3 5
2 2
Multiply to get a power of ten in the denominator.


0.6
18 25
B.
Multiply to get a power of ten in the denominator.
18 25
4 4


0.72
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You can also use place value to write a
terminating decimal as a fraction. Use the place
value of the last digit to the right of the
decimal point as the denominator of the fraction.
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Additional Example 3 Writing Decimals as
Fractions
Write each decimal as a fraction in simplest form.
B. 1.55
A. 0.018
18 1,000
155 100
0.018
1.55
18 2 1,000 2
155 5 100 5


31 20
11 20
9 500
or 1


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Check It Out! Example 3
Write each decimal as a fraction in simplest form.
B. 1.30
A. 0.015
15 1,000
130 100
0.015
1.30
130 10 100 10
15 5 1,000 5


3 200
3 10
13 10

or 1

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Additional Example 4 Sports Application
A football player completed 1,546 of the 3,875
passes he attempted. Find his completion rate.
Write your answer as a decimal rounded to the
nearest thousandth.
0.3989
Divide the numerator by the denominator.
His completion rate is 0.399.
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Check It Out! Example 4
Johnny Unitas, a former professional quarterback,
completed 2,830 of the 5,186 passes he attempted.
Find his completion rate. Write your answer as a
decimal rounded to the nearest thousandth.
0.5456
Divide the numerator by the denominator.
His completion rate is 0.546.