Question

The lifespans (in years) of ten beagles were 11; 9; 9; 8; 11; 12; 12; 10; 10; 11. Calculate the mean of the dataset.

Question 1 options:

1)

103

2)

1.34

3)

10.3

4)

10

5)

10.5

Question 2 (1 point)

Saved

Ten students took a statistics final and their scores were 84.9; 80.1; 78.7; 77; 75.7; 79.1; 80.6; 79.4; 73.8; 79.2. Calculate the coefficient of variation of the dataset.

Question 2 options:

1)

0.038

2)

235.943

3)

-75.858

4)

81.842

5)

5.985

Question 3 (1 point)

The average domestic economy car gets around 28.4 miles per gallon (MPG) with a standard deviation of 2.65. Suppose domestic manufacturers all vow to increase fuel economy over the next 2 years. If successesful, 3.4 is added to every observation in the dataset. What is the new mean?

Question 3 options:

1)

3.4

2)

96.56

3)

8.35

4)

31.8

5)

28.4

Question 4 (1 point)

Saved

Suppose the average golfer drives the ball around 200.99 yards with a standard deviation of 8.06. However, when given a new type of driver, every observation in the dataset is multiplied by 1.18. What is the new mean?

Question 4 options:

1)

1.18

2)

170.33

3)

237.17

4)

202.17

5)

200.99

Question 5 (1 point)

Suppose that the average and standard deviation of the number of points scored in an NBA game per player are 18.63 and 5.28, respectively. Calculate an interval that is symmetric around the mean such that it contains approximately 68% of players scores. Assume that the points scored has a normal distribution.

Question 5 options:

1)	(8.07, 29.19)

2)	(18.63, 5.28)

3)	(23.91, 13.35)

4)	(29.19, 8.07)

5)	(13.35, 23.91)

Question 6 (1 point)

Suppose that the middle 68% of score on a statistics final fall between 68.35 and 86.07. Give an approximate estimate of the standard deviation of scores. Assume the scores have a normal distribution.

Question 6 options:

1)

77.21

2)

17.72

3)

-8.86

4)

8.86

5)

4.43

Question 7 (1 point)

The stock price for International Business Machines (IBM) historically has followed an approximately normal distribution (when adjusting for inflation) with a mean of $155.483 and standard deviation of $4.0278. What is the probability that on a selected day the stock price is between $155.71 and 159.48?

Question 7 options:

1)

0.0059

2)

0.5225

3)

0.3170

4)

0.1605

5)	We do not have enough information to calculate the value.

Question 8 (1 point)

Suppose that the mean and standard deviation of the scores on a statistics exam are 75.3 and 6.2, respectively, and are approximately normally distributed. Calculate the proportion of scores above 77.

Question 8 options:

1)

0.1735

2)	We do not have enough information to calculate the value.

3)

0.8265

4)

0.3920

5)

0.6080

Question 9 (1 point)

Suppose that the mean and standard deviation of the scores on a statistics exam are 80.1 and 5.07, respectively, and are approximately normally distributed. Calculate the proportion of scores between 72 and 78.

Question 9 options:

1)

0.0551

2)

0.0204

3)	We do not have enough information to calculate the value.

4)

0.6606

5)

0.2843

Answer 1