Hourly wages in a particular industry are normally distributed with a mean of $13.20 and a standard deviation of $2.50. A random sample of 40 workers was taken from a certain fi rm in this industry, and the sample mean was $12.90. We would like to test the claim that the wages are less than the industry average of $13.20.
What is the alternative hypothesis for this problem (H1)?
What is the value of the test statistic for this problem?
What is the rejection region for testing this claim at = :01?