The Dean of a Business School Claims That the Average

Multiple Choice

The dean of a business school claims that the average starting salary of its graduates is more than $50,000. It is known that the population standard deviation is $10,000. Sample data on the starting salaries of 20 randomly selected recent graduates yielded a mean of $55,000. What is the value of the sample test statistic?

A) z = 2.24
B) t = 7.2
C) t = 5.04
D) t = 2.24