1. Math 8 – Unit Rates and Proportions
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2. CC3: Proportional Reasoning

3. There is a lot of candy around at Halloween time!

7. What mathematical questions come
to mind?

8. Which is the best deal on candy?
When shopping for Halloween candy, there are so many choices of mixed bags of candy.
What information do you need to determine the best deal?
If you were given that information, how would you figure out the best deal?

9. Which is the best deal on candy?

10. Some Definitions Unit – A quantity used as a standard of measurement
Example: A foot, a second, a liter, a decibel
Your Example:

11. Some Definitions
Ratio – A measurement compared against another measurement
Example: It takes Mr. Horan 5 days to grade 133 tests.
Your Example:

12. Some Definitions
Unit Rate – A measurement compared against another measurement where one of the measurements MUST BE EQUAL TO ONE.
Example: 60 miles per hour, 4 tablespoons of honey per batch of pizza dough, $15.00 per notebook
Your Example:

13. Examples of Unit Rates
Mike spends $3.00 on two candy bars. How much did he spend per candy bar?

14. Examples of Unit Rates
Mike spends $3.00 on two candy bars. How much did he spend per candy bar?
He spent $1.50 per candy bar.

15. Examples of Unit Rates
Mike spends $3.00 on two candy bars. How much did he spend per candy bar?
He spent $1.50 per candy bar.
Danielle drove 150 miles in 5 hours. How fast was she driving in miles per hour?

16. Examples of Unit Rates
Mike spends $3.00 on two candy bars. How much did he spend per candy bar?
He spent $1.50 per candy bar.
Danielle drove 150 miles in 5 hours. How fast was she driving in miles per hour?
She drove 30 miles per hour.

17. Examples of Unit Rates
Mike spends $3.00 on two candy bars. How much did he spend per candy bar?
He spent $1.50 per candy bar.
Danielle drove 150 miles in 5 hours. How fast was she driving in miles per hour?
She drove 3 miles per hour.
How many miles do you walk to school? How long does it take you?