AP Statistics Name______

Test: notes

Part I. Answer the following.

1. A researcher wishes to estimate, with 90% confidence, the number of people who own a home computer. The researcher wishes to be within 3% of the true proportion. Find the minimum sample size that will be needed.

2. Kellogg’s Froot Loops cereal comes in six fruit flavors: orange, lemon, cherry, raspberry, blueberry, and lime. Charise poured out her morning bowl of cereal and methodically counted the number of cereal pieces of each flavor. The number of each flavor is shown below. Test the null hypothesis that the population of Froot Loops produced by Kellogg’s contains an equal proportion of each flavor.

3. What does 95% confidence level mean? (in general)

4. What is a p-value?

5. What happens to the size of the confidence interval as the sample size is increased?

6. Give the three properties of a sampling distribution of a mean.

a.

b.

c.

7. What happens to the power of a test when

a. the sample size is decreased

b. the level is decreased

8. The equation of the least squares regression line for a set of points in a scatter plot is given by . The point (8, 18) is one point on this scatter plot. What is the residual for this point?

9. The data for age and blood pressure for 20 adults between 25 and 30 were collected. The results are shown below.

a. Find and interpret the coefficient of determination.

b. Find and interpret the correlation coefficient.

c. Is there a linear relationship between blood pressure and age? Use statistical justification.

d. Find an estimate for the slope using a 95% confidence interval.

10. If the P(A) = 0.4 and the P(B) = 0.3, find the following if

a. A and B are mutually exclusive:

i). P(A Ç B) = ______ii) P(AÈ B) = ______

b. A and B are independent:

i). P(A Ç B) = ______ii) P(AÈ B) = ______

11. The following represents the different classes and their favorite course.

Math / English / Science / History
Freshmen / 40 / 30 / 22 / 18
Sophomore / 38 / 22 / 28 / 35
Junior / 70 / 18 / 21 / 31
Senior / 55 / 28 / 32 / 14

a. P(Math) = ______b. P(History | Junior) = ______

c. P(English or Senior) = ______d. P(Science or Math) = ______

12. Are the events “Likes History” and being a “Junior” independent? Show your work.