1. Are the following two variables positively associated, negatively associated or not associated? Let X be how much gas you have in your tank (in gallons). Let Y be the cost to fill your gas tank.
a. The two variables are positively associated.
b. The two variables are negatively associated.
c. The two variables are not associated.

2. The scatterplots below display three bivariate data sets
The scatterplots below display three bivariate data sets. The correlation coefficients for these data sets are .03, .68, and Which scatter plot corresponds to the data set with r = .03? 1 2 3

3.   Gas mileage and weight were recorded for each automobile in a sample of 20 compact cars. There was a strong negative correlation, with r = Based on the value of r, it is reasonable to conclude that increasing the weight of a compact car causes a decrease in gas mileage.
True
False

4. Below is a plot of the Olympic gold-medal-winning performance in the high jump (in inches) for the years 1900 to From this plot, the correlation between the winning height and year of the jump is
a. about 0.95.
b. about 0.10.
c. about

5. All but one of the following statements contain a blunder
All but one of the following statements contain a blunder. Which one does not contain a blunder?
“There is a correlation of r = between the position a football player plays and his or her weight.”
“The correlation between amount of fertilizer and yield of tomatoes was found to be r = ”
“The correlation between the gas mileage of a car and its weight is r = 0.71 gallon-pounds.”

6. I wish to determine the correlation between the height (in inches) and weight (in pounds) of 21-year-old males. To do this I measure the height and weight of two 21-year-old men. The measured values are The correlation, r, computed from the measurements on these males, is
1.0.
-1.0.
near 0, because the heights and weights of the men are similar.

7. Answers: B, B, B, A, B, B