For Exercises 8.1 and 8.2, see page 419; for 8.3 and 8.4, see page 421; for 8.5 to 8.7, see page 423; for 8.8 to 8.11, see pages 425–426; for 8.12, see page 426; for 8.13 and 8.14, see page 429; and for 8.15 and 8.16, see page 431.
8.5 Use plus four for net jobs.
Refer to Example 8.3 (pages 420–421). Compute the plus four 95% confidence interval, and compare this interval with the one given in that example.
8.5
(0.4575, 0.5025). This plus-four interval is quite close to the original interval of (0.458, 0.502).