For Exercises 19–22, do the following:
21. Test whether the population proportion differs from 0.5. A random sample of size 900 yields 475 successes.
9.5.21
(a) We have and , so we may use the test for proportions. (b) Reject if the . (c) 1.67 (d) (e) Since the is not , we do not reject . There is insufficient evidence that the population proportion is not equal to 0.5.