Problem D.

The starting salaries of individuals having an MBA degree is normally distributed with a mean of $40,000 and a standard deviation of $10,000.

ANSWER QUESTIONS 15 - 17 BELOW.

15. What is the probability that a randomly selected individual with an MBA degree will get a starting salary greater than $30,000?

a. 0.3413 b. 0.1587 c. -1.0 d. 0.8413

16. What is the probability that a randomly selected individual with an MBA degree will get a starting salary of less than $47,500?

a. 0.7734 b. 0.75 c. 0.2734 d. 0.2266

17. What percentage of MBAs will get starting salaries between $34,000 to $46,000?

a. 54.86% b. 45.14% c. 27.43% d. 22.57%

Problem E

A local university wants to estimate the average time/week spent on computer laboratory terminals by each student.Data was collected for a sample of 81 students. The sample mean is 9 hours and standard deviation is 1.2 hours.

ANSWER QUESTIONS 18 - 19 BELOW.

18. The standard error of the mean is:

a. 7.5 b. 0.014 c. 0.16 d. 0.133

19. With 0.95 probability the margin of error is approximately:

a. 0.26 b. 1.96 c. 1.21 d. 1.64

20. The 95% confidence interval is:

a. 7.04 to11.096 hours

b. 7.36to 10.64 hours

c. 7.8 to 10.2 hours

d. 8.74to 9.26 hours

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Problem F

The manager of a grocery store claims that the average time that customers spend in checkout lines is 20 minutes or less. A sample of 36 customers is taken. The average time spent on checkout lines for the sample is 24.6 minutes; and the sample standard deviation is 12 minutes. Conduct a hypothesis test (at 0.05 level of significance) to determine if the mean waiting time for the customer population is significantly more than 20 minutes.

ANSWER QUESTIONS 21 THROUGH 24 BELOW.

21. The correct hypotheses for the test are:

a. H₀ is: m 20; H_a is: m <20

b. H₀ is: m 20; H_a is: m > 20

c. H₀ is: m >20; H_a is: m 20

d. H₀ is: m <20; H_a is: m 20

22. The observed value of the test statistic is:

a. 2.3 b. 0.38 c. -2.3 d. -0.38

23. The p-value is:

a. 0.5107 b. 0.0214 c. 0.0137 d. 0.4893

24. The null hypothesis should:

a. not be rejected

b. be rejected

c. the test is inconclusive

d. none of the above answers are correct