Question

This question has 4 parts 1 - 4 below. Enter your answer for each part.

A random sample of 25 employees for the retailer showed a sample mean of 9.2 minutes and a standard deviation of 2 minutes. Assume that the time spent by employees on personal phone calls is normally distributed. Let μ denote the mean time spent by employees on personal phone calls.

(1) Find the critical value from the table that is used to compute a 95% confidence interval for μ.

(2) An employee group for a national retailer claims that the mean time spent by employees on personal phone calls is less than 10 minutes per day. Specify the correct form of the alternative hypotheses you would use to investigate the employee group's claim. Enter your answer as a single letter: A, B, or C.

A) H1: µ < 0 B) H1: µ ╪ 0 C) H1: µ > 0   

(3) Find the value of the test statistic, accurate to one decimal place, used to test the employees group's claim.

(4) Enter the critical value from the table used to define the rejection region at α=0.05.   

Answer 1