Some people who bought ABC server systems complained about having received defective systems. The industry standard for such systems has been ninety-five percent non-defective systems. In a sample of 82 units sold, 4 units were defective.

1. Compute the proportion of defective items in the sample.
2. Compute the standard error of p¯.
3. Compute the test statistic for p¯.
4. Compute the critical value at 97% confidence
5. Using the critical value approach, test to see if the percentage of defective systems produced by ABC has exceeded the industry standard.
6. Show that the p-value approach results in the same conclusion as that of part b.
7. What is your conclusion? Is ABC significantly better or worse than the industry?