For Exercises 21–26, assume that the populations are independent and normally distributed. Perform the indicated hypothesis tests using the critical-value method. For each exercise

  1. State the hypotheses.
  2. Find the critical value(s) and state the rejection rule.
  3. Find .
  4. State the conclusion and interpretation.

Question 10.181

25.

10.4.25

(a) (b) and . Reject if or if . (c) . (d) Since is , we reject . There is evidence at the level of significance that the population standard deviation of Population 1 differs from the population standard deviation of Population 2.