1. In this chapter, we will look at using the standard deviation as a measuring stick and some properties of data sets that are normally distributed.

4. In the year 2009, cars sold in the United States had an average of 135 horsepower with a standard deviation of 40 horsepower. (a) Find the z-score for a car with 120 horsepower. (b) Find the z-score for a car with 200 horsepower. (c) A certain car has z-score of 1.2. How much horsepower does it have? (d) A certain car has z-score of 0.6. How much horsepower does it have?

5. Adult Dalmatians have an average weight of 52 pounds with a standard deviation of 6 pounds. Adult German Shepherds have an average weight of 77 pounds with a standard deviation of 3.6 pounds. Which is more unusual, an adult Dalmatian weighing 63 pounds or an adult German Shepherd weighing only 68 pounds?

6.   +   + 2   + 3   -   - 2   - 3 

7. The standard normal curve is. This is commonly called the z–curve. It has shape below: 0 1 2 3 -2 -3

8. For a normal distribution: ≈ 68% of values fall within one standard deviation of the mean ≈ 95% of values fall within two standard deviations of the mean ≈ 99.7% of values fall within three standard deviations of the mean