According to the U.S. Department of Labor, the median salary for a chiropractor in the United States is $81,500 per year. A group of recent graduates employed in the state of Colorado believe this amount is too low. In a random sample of 18 chiropractors who recently graduated, 13 began with a salary of more than $81,500. Is it reasonable to conclude that the starting salary in Colorado is more than $81,500?

a. State the null and alternate hypotheses.

b. State the decision rule. Use the .05 significance level.

c. Test the hypothesis and interpret the results.