Reference no: EM132955442

University X has 20,000 students, of which 9000 are men, and 11,000 are women. You collected independent simple random samples from men and women, and recorded how much money each respondent spent on cellular telephone service in a month.

You got the following results:

Men: Sample size = 100, sample mean = $40, sample standard deviation = $20
Women: Sample size = 100, sample mean = $55, sample standard deviation = $15

Problem 1: You want to test the null hypothesis that the total expenditure on cellular telephone service by all the 11000 women, combined, in a month does not exceed $500,000. Please write down the correct expression of the corresponding null hypothesis. Discuss the potential Type I and Type II error.

Problem 2: At a 99% level of confidence, test the above null hypothesis, that the total expenditure on cellular telephone service by all the 11000 women, combined, in a month does not exceed $500,000. Note: the corresponding Z statistic for 99% level of confidence is 2.33. (Show details of work)

Problem 3: You want to test the null hypothesis that on the average, the monthly expenditure on cellular telephone service by a woman does not exceed the monthly expenditure on cellular telephone service by a man by more than $10. Please write down the correct expression of the corresponding null hypothesis (You do not need to test this one)