Suppose we wish to test H0: p = .8 versus Ha: p > .8 and that a random sample of n = 400 gives a
sample proportion = .86.
a Test H0 versus Ha at the .05 level of significance by using a rejection point. What do you conclude?
b Find the p-value for this test.
c Use the p-value to test H0 versus Ha by setting alpha equal to .10, .05, .01, and .001. What do you
conclude at each value of alpha?
In this solution, formulas, calculation details and explanations are provided for two problems. The first problem finds 95 and 99 percent confidence intervals for a mean. The second problem conducts a hypothesis test for a mean.