A large university reports that the mean annual income of parents of an entering class is $91,600. To see how this compares to his university, the president commissions a survey of n = 31 randomly selected families, and finds that their average income is x = $88,500 with a sample standard deviation of s = $10,000. Can the president conclude that the average family income at his school is significantly different than the population mean family income of the reported university?