For Exercises 19–22, do the following:

  1. Check the normality conditions.
  2. State the hypotheses and the rejection rule for the -value method, using level of significance .
  3. Find .
  4. Find the -value.
  5. Compare the -value with level of significance . State the conclusion and the interpretation.

Question 9.286

20. Test whether the population proportion is less than 0.2. A random sample of size 400 yields 75 successes.