increased significantly? Test at alpha = .10. Sample SizeNo. Majoring in BusinessPrevious Sample25050Present Sample30069Answer:H0: P1- P2≤0Ha: P1- P2> 0Z = 1.86;p-value = 0.0628; reject H039.The following information regarding the number of semester hours taken from random samples of day and evening students is provided.DayEveningx1612s43n4037Develop a 95% confidence interval estimate for the difference between the mean semester hours taken by the two groups of students.Answer:3.269 to 4.73140.The following data present the number of computer units sold per day by a sample of 6 salespersons before and after a bonus plan was implemented.
28Chapter TenSalespersonBeforeAfter136275366487578698At 95% confidence, test to see if the bonus plan was effective. That is, did the bonus plan actually increasesales?Answer:H0: μ≤0Ha: μ> 0t = 0; p-value=1.0, do not reject H0 41.Zip, Inc. manufactures Zip drives on two different manufacturing processes. Because the management of this company is interested in determining if process 1 takes less manufacturing time, they selected independent samples from each process. The results of the samples are shown below.Process 1Process 2Sample Size2722Sample Mean (in minutes)1014Sample Variance1625 42.A credit company has gathered information regarding the average amount owed by people under 30 years old and by people over 30 years. Independent random samples were taken from both age groups. You are given the following information.Under 30Over 30x600550
Inferences With Two Populations 29n200300σ2361400Construct a 95% confidence interval for the difference between the average amounts owed by the two age groups.Answer:46.528 to 53.47243.In order to estimate the difference between the average age of male and female employees at the Young Corporation, the following information was gathered.MaleFemaleSample Size3236Sample Mean2523Sample Standard Deviation46Develop a 95% confidence interval estimate for the difference between the average age of male and female employees at the Young Corporation.Answer:-0.449 to 4.44944.A recent Time magazine reported the following information about a sample of workers in Germany and the United States.United StatesGermanyAverage length of workweek (hours)4238Sample Standard Deviation56Sample Size600700We want to determine whether or not there is a significant difference between the average workweek in the United States and the average workweek in Germany.