The personnel director of a large corporation wishes to study absenteeism among clerical workers at the corporation's central office during the year.A random sample of 50 clerical workers reveals the following:

Absenteeism average: X-bar = 9.7 days.

Also, past data indicates that the population standard deviation seems to be 1.2 days. The director thinks that actual population mean is 10.5 days.

a)Construct the hypotheses to test the director's claim.

H0:

Ha:

b) Test the hypotheses a conclusion with a confidence level of 90%.

c) Conclusion: