Has the cost to outsource a standard employee background check changed? A random sample of 10 companies in spring 2010 showed a sample average of $105 with a sample standard deviation equal to $32. A random sample of 10 different companies in spring 2012 resulted in a sample average of $75 with a sample standard deviation equal to $45.
(a) Conduct a hypothesis test to test the difference in sample means with a level of significance equal to .05. Assume the population variances are not equal.
(b) Discuss why a paired sample design might have made more sense in this case.