10 terms

1. The scatter plot shows the number of hats and scarves each knitter sold at a knitting show.

How many hats did the knitter who sold 9 scarves sell?

https://static.k12.com/calms_media/media/1397500_1398000/1397815/1/418825d868846eca6c43dba49c399c2ab447d68a/PRM_A_03_19_ScatterPlot_Q1.jpg

a.) 2

b.) 3

c.) 4

d.) 6

How many hats did the knitter who sold 9 scarves sell?

https://static.k12.com/calms_media/media/1397500_1398000/1397815/1/418825d868846eca6c43dba49c399c2ab447d68a/PRM_A_03_19_ScatterPlot_Q1.jpg

a.) 2

b.) 3

c.) 4

d.) 6

Answer: (a) 2

2. Which best describes the association between variables x and y?

https://static.k12.com/calms_media/media/1397500_1398000/1397818/1/fd82cc21f31c065f406ab7202664413c5db93364/PRM_A_03_19_ScatterPlot_Q2.jpg

a.) strong positive

b.) strong negative

c.) weak positive

d.) weak negative

https://static.k12.com/calms_media/media/1397500_1398000/1397818/1/fd82cc21f31c065f406ab7202664413c5db93364/PRM_A_03_19_ScatterPlot_Q2.jpg

a.) strong positive

b.) strong negative

c.) weak positive

d.) weak negative

Answer: (b) strong negative

3. For the data shown in the scatter plot, which is the best estimate of r?

https://static.k12.com/calms_media/media/1397500_1398000/1397820/1/3a57bf43d7c1cfe371d8e471ae37dbb317b74c80/PRM_A_03_19_ScatterPlot_Q3-2.jpg

a.) 0

b.) -1

c.) 1

d.) 0.5

https://static.k12.com/calms_media/media/1397500_1398000/1397820/1/3a57bf43d7c1cfe371d8e471ae37dbb317b74c80/PRM_A_03_19_ScatterPlot_Q3-2.jpg

a.) 0

b.) -1

c.) 1

d.) 0.5

Answer: (a) 0

4. In one study, it was found that the correlation coefficient between two variables is negative 0.32.

Which statement is true?

a.) There is a weak positive association between the variables.

b.) There is a weak negative association between the variables.

c.) There is strong positive association between the variables.

d.) There is a strong negative association between the variables.

Which statement is true?

a.) There is a weak positive association between the variables.

b.) There is a weak negative association between the variables.

c.) There is strong positive association between the variables.

d.) There is a strong negative association between the variables.

Answer: (b) There is a weak negative association between the variables.

5. Rounded to three decimal places, what is the value of r for this data set?

https://static.k12.com/calms_media/media/1397500_1398000/1397808/1/86fa304a01fe67bc1635587ff2c5e2e11a8ade6e/PRM_A_03_19_BivariateData_Q5.jpg

a.) 0.870

b.) 0.897

c.) 0.978

d.) 0.989

https://static.k12.com/calms_media/media/1397500_1398000/1397808/1/86fa304a01fe67bc1635587ff2c5e2e11a8ade6e/PRM_A_03_19_BivariateData_Q5.jpg

a.) 0.870

b.) 0.897

c.) 0.978

d.) 0.989

Answer: (d) 0.989

6. A study of several cities shows a positive correlation between the percent of people late to work and the amount of pollution on the roadways.

Which statement is most likely true?

a.) Pollution makes people late to work.

b.) People who tend to be late make more pollution than those who tend to be on time.

c.) The correlation is due to a third variable: traffic.

d.) The correlation is due to a third variable: cost of windshield wiper fluid.

Which statement is most likely true?

a.) Pollution makes people late to work.

b.) People who tend to be late make more pollution than those who tend to be on time.

c.) The correlation is due to a third variable: traffic.

d.) The correlation is due to a third variable: cost of windshield wiper fluid.

Answer: (c) The correlation is due to a third variable: traffic.

7. The regression equation y = 4x + 20 approximates the number of people attending a picnic, y, given the number of flyers used to advertise it, x.

Which statement is true?

a.) For every extra person attending a picnic, the number of flyers used to advertise it increases by 20.

b.) For every extra person attending a picnic, the number of flyers used to advertise it increases by 4.

c.) For every extra flyer used in advertising, the attendance increases by 20 people.

d.) For every extra flyer used in advertising, the attendance increases by 4 people.

Which statement is true?

a.) For every extra person attending a picnic, the number of flyers used to advertise it increases by 20.

b.) For every extra person attending a picnic, the number of flyers used to advertise it increases by 4.

c.) For every extra flyer used in advertising, the attendance increases by 20 people.

d.) For every extra flyer used in advertising, the attendance increases by 4 people.

Answer: (d) For every extra flyer used in advertising, the attendance increases by 4 people.

8. The regression equation y equals negative 0.414 x plus 106.55 approximates the percent of people in an audience who finish watching a documentary, y, given the length of the film in minutes, x.

Which percent is the best prediction for the percent of people in an audience who will finish watching a documentary that is 180 minutes long?

a.) 75%

b.) 67%

c.) 32%

d.) 26%

Which percent is the best prediction for the percent of people in an audience who will finish watching a documentary that is 180 minutes long?

a.) 75%

b.) 67%

c.) 32%

d.) 26%

Answer: (c) 32%

9. The correlation coefficient r between an employee's age, x, and yearly salary, y, is 0.633.

What percent of the variation in yearly salaries can be explained by differences in the employees' ages?

a.) 15.8%

b.) 31.7%

c.) 40.1%

d.) 63.3%

What percent of the variation in yearly salaries can be explained by differences in the employees' ages?

a.) 15.8%

b.) 31.7%

c.) 40.1%

d.) 63.3%

Answer: (c) 40.1%

10. The regression equation y equals 3.648 times 1.182 to the power of x approximates the cost to go on a safari, y, given the number of years since it opened in 2005, x.

Which is the best estimate for the cost of a vehicle to drive through the safari in 2013?

a.) $7.46

b.) $12.44

c.) $13.90

d.) $34.50

Which is the best estimate for the cost of a vehicle to drive through the safari in 2013?

a.) $7.46

b.) $12.44

c.) $13.90

d.) $34.50

Answer: (c) $13.90