2. Main Idea and New Vocabulary
Example 1: Identify Proportional Relationships
Example 2: Identify Proportional Relationships
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3. Identify proportional and nonproportional relationships.
Main Idea/Vocabulary

4. Identify Proportional Relationships
BUSINESS A cleaning service charges $45 for the first hour and $30 for each additional hour. Is the fee proportional to the number of hours worked? Make a table of values to explain your reasoning.
Example 1

5. Identify Proportional Relationships
For each number of hours, write the relationship of the cost and the number of hours worked as a ratio in simplest form.
Example 1

6. Identify Proportional Relationships
Answer: Since the ratios of the two quantities are not the same, the cleaning fee is not proportional to the number of hours worked.
Example 1

7. CARPET CLEANING A carpet cleaning company charges $20 per room to steam clean the carpet plus a $25 service call. Is the cost proportional to the number of rooms cleaned?
A. Yes; the ratios are the same, $20 per room.
B. Yes; the ratios are the same, $25 per room.
C. Yes; the ratios are the same, $45 per room.
D. No; the ratios are not the same.
Example 1 CYP

8. Identify Proportional Relationships
BAKING A recipe for jelly frosting calls for
cup of jelly and 1 egg white. Is the number of egg whites used proportional to the cups of jelly used? Make a table of values to explain your reasoning.
Example 2

9. Identify Proportional Relationships
Find the amount of jelly and egg whites needed for different numbers of batches and make a table to show these jelly and egg white measures.
Example 2

10. Identify Proportional Relationships
For each number of cups of jelly, write the relationship of the number of cups of jelly and the number of egg whites.
Example 2

11. Identify Proportional Relationships
Answer: All of the ratios between the two quantities can be simplified to . The amount of jelly used is proportional to the number of egg whites used.
Example 2

12. A. Yes; the ratios between the two quantities are all equal to .
LEMONADE A recipe for lemonade is shown. Is the number of lemons used proportional to the amount of sugar used?
A. Yes; the ratios between the two quantities are all equal to .
B. Yes; the ratios between the two quantities are all equal to .
C. Yes; the ratios between the two quantities are all equal to
D. No; the ratios between the two quantities are not the same.
Example 2 CYP