The Bureau of Labor Statistics Reported That the Average Yearly

Essay

The Bureau of Labor Statistics reported that the average yearly income of dentists in the year 2009 was $110,000.A sample of 81 dentists,which was taken in 2010,showed an average yearly income of $120,000.Assume the standard deviation of the population of dentists in 2010 is $36,000.
a.We want to test to determine if there has been a significant increase in the average yearly income of dentists.Provide the null and the alternative hypotheses.
b.Compute the test statistic.
c.Determine the p-value;and at 95% confidence,test the hypotheses.