Lesson 10­5 Ratios as Decimals.notebook
January 13, 2017
Warm Up:
Name three equivalent ratios to each of the following.
1. 2. Write each ratio in simplest form.
3.
4.
5. Your class visits the zoo. Your friend says that the ratio of elephants to giraffes is 3/8. You describe the relationship of elephants to giraffes as 9/24. Can both you and your friend be correct?
1
Lesson 10­5 Ratios as Decimals.notebook
January 13, 2017
Agenda:
1. Launch Question
2. Notes on Lesson 10­5 Ratios as
Decimals
3. Independent Work: Lesson 10­5
Worksheet
4. Mrs Shire's Symbaloo
2
Lesson 10­5 Ratios as Decimals.notebook
January 13, 2017
Launch:
Two students take turns recording daily rain totals. When the teachers sees their work, she exclaims, "Give me the daily results and total rainfall in one way!"
Show how you would revise the results for the teacher.
3
Lesson 10­5 Ratios as Decimals.notebook
January 13, 2017
Focus Question:
Why might you want to write a
ratio as a decimal?
4
Lesson 10­5 Ratios as Decimals.notebook
January 13, 2017
Lesson 10 ­ 5
Ratios As Decimals
To write a ratio as a decimal, first write
equation ­
the
ratio as a fraction. Then write the
fraction as a decimal.
A ratio written as a decimal is a
comparison of the decimal to 1.
0.5 means 0.5 to 1.
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Lesson 10­5 Ratios as Decimals.notebook
January 13, 2017
Lesson 10 ­ 5
Ratios As Decimals
Recall: Write each of the following fractions as decimals.
equation ­
a.)
b.)
6
Lesson 10­5 Ratios as Decimals.notebook
January 13, 2017
Lesson 10 ­ 5
Ratios As Decimals
Write the following ratio as a fraction and a
decimal.
equation ­
7
Lesson 10­5 Ratios as Decimals.notebook
January 13, 2017
Lesson 10 ­ 5
Ratios As Decimals
Write the following ratio as a fraction and a
decimal.
equation ­
8
Lesson 10­5 Ratios as Decimals.notebook
January 13, 2017
Lesson 10 ­ 5
Ratios As Decimals
Example 1: The aspect ratio of an image is the ratio
of the width of the image to the height of the
image. The table shows the aspect ratios for three
computer monitor settings. Complete the table.
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Lesson 10­5 Ratios as Decimals.notebook
January 13, 2017
Lesson 10 ­ 5
Ratios As Decimals
Recall: Write each of the following decimals as fractions.
equation ­
a.) 0.35
b.) 1.7
10
Lesson 10­5 Ratios as Decimals.notebook
January 13, 2017
Lesson 10 ­ 5
Ratios As Decimals
Write the following ratio as a fraction
in simplest form.
equation ­
11
Lesson 10­5 Ratios as Decimals.notebook
January 13, 2017
Lesson 10 ­ 5
Ratios As Decimals
Example 2: Write each of the following ratios as
fractions in simplest form.
a.)
b.)
12
Lesson 10­5 Ratios as Decimals.notebook
January 13, 2017
Lesson 10 ­ 5
Ratios As Decimals
Example 2: Write each of the following ratios as
fractions in simplest form.
c.)
d.)
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Lesson 10­5 Ratios as Decimals.notebook
January 13, 2017
Lesson 10 ­ 5
Ratios As Decimals
In baseball, a player's batting average is the
ratio
of the number of hits to the number of at
equation ­
bats.
A new player's batting average is 0.350. The
player has 60 at bats. How many hits does the
player have?
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Lesson 10­5 Ratios as Decimals.notebook
January 13, 2017
Lesson 10 ­ 5
Ratios As Decimals
Example 3: Which player has the best batting
average? Explain how you found your answer.
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Lesson 10­5 Ratios as Decimals.notebook
January 13, 2017
Lesson 10 ­ 5
Ratios As Decimals
Lesson Quiz:
Write each of the following ratio as a fraction and a decimal.
1. 2. Write each ratio as a fraction in simplest form.
3.
4.
16
Lesson 10­5 Ratios as Decimals.notebook
January 13, 2017
Classwork:
1. Independent Work: Lesson 10­5
Worksheet
2. Mrs Shire's Symbaloo
17