For Exercises 21–30, perform the test for using level of significance a by doing the following steps:

  1. State the hypotheses and the rejection rule.
  2. Calculate .
  3. Find the -value.
  4. State the conclusion and the interpretation.

Question 9.131

25.

9.3.25

(a) . We will reject if the . (b) (c) (d) The is . Therefore we reject . There is evidence at level of significance that the population mean is less than 500.