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Ratios and Rates

Goals: In this lesson, youll write

ratios as fractions in simplest formand determine unit rates.

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5-Minute Check

1. Determine the domain and range of therelation {(-1,2), (-3,4), (2,2), (-3,2)}. Is therelation a function?

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5-Minute Check

1. Determine the domain and range of therelation {(-1,2), (-3,4), (2,2), (-3,2)}. Is therelation a function?

D = {-3,-1,2}; R = {2,4}; no

2.

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5-Minute Check

1. Determine the domain and range of therelation {(-1,2), (-3,4), (2,2), (-3,2)}. Is therelation a function?

D = {-3,-1,2}; R = {2,4}; no

2. Find the slope of the line that containsA(3,5) and B(-2,-6).

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5-Minute Check

1. Determine the domain and range of therelation {(-1,2), (-3,4), (2,2), (-3,2)}. Is therelation a function?

D = {-3,-1,2}; R = {2,4}; no

2. Find the slope of the line that containsA(3,5) and B(-2,-6).

11/5

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5-Minute Check

Graph each equation or inequality.

3. y = 3x1

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5-Minute Check

Graph each equation or inequality.

3. y = 3x1

Markings should be placedon coordinates (1,2) and(0,-1). A line should bemade going across them,extending in bothdirections.

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5-Minute Check

4. x + y > 6

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5-Minute Check

4. x + y > 6

A dotted line shouldgo across +6 on boththe y-axis, and onthe x-axis.

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5-Minute Check

4. x + y > 6

A dotted line shouldgo across +6 on boththe y-axis, and onthe x-axis.

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5-Minute Check

4. x + y > 6

A dotted line shouldgo across +6 on boththe y-axis, and onthe x-axis. Then, theoutside of that lineshould be shaded.

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Ratios and Rates

Example 1.

Many grocery stores list the unit price ofitems on the shelf tag so that customersmay compare similar items. The cost of a12-ounce box of Cheerios is $3.29. a storebrand cereal that is similar to Cheerios

costs $4.89 for an 18-ounce box. Whichcereal has a lower per-ounce cost?

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Ratios and Rates

Cheerios

329cents/12(ounces) =

Store Brand

489cents/18(ounces) =

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Ratios and Rates

Cheerios

329cents/12(ounces) = 27.417

Store Brand

489cents/18(ounces) = 27.167

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Ratios and Rates

The cost is about 27.4 cents per ounce forCheerios. The store brand is about 27.2

cents per ounce.

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Ratios and Rates

The cost is about 27.4 cents per ounce forCheerios. The store brand is about 27.2

cents per ounce.So the store brand is less

expensive per ounce.

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Ratios and Rates

What is the difference between ratio and

rate?

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Ratios and Rates

Write a ratio that compares the number ofstudents in your school to the number of

teachers. Then express this ratio as a unit

rate.

Animas High has 10 teachers

Animas High has 96 students

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Ratios and Rates

Describe and give an example of a unit rate.

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Ratios and Rates

Express each ratio as a unit rate.

1. 12 pounds lost in 5 weeks

2. $2.29 for a 6 pack of cola3. 99 for a dozen

4. 6 inches of rain in 24 hours

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Ratios and Rates

Assignment: 1632 E, 3346 A