1. In Exercise 9.84, a small-scale preliminary survey has indicated that no more than 20% of the televi- sion households will tune in to the first episode of the miniseries. Given this information, how large must the sample be?
2. In a survey of 500 U.S. adults, 45% of them said that lounging at the beach was their "dream vacation." Assuming this to be a simple random sample of U.S. adults, construct and interpret the 95% and 99% confi- dence intervals for the proportion of U.S. adults who con- sider lounging at the beach to be their dream vacation.
3. For the following simple random sample of house- hold incomes (thousands of dollars) from a large county, construct and interpret the 90% and 95% confidence intervals for the population mean. The data are also in file XR09087.
58.3 50.0 58.1 33.5 51.1 38.1 42.3 60.4 55.8 46.2
|
40.4
|
52.5
|
51.3
|
47.5
|
48.5
|
59.3
|
40.9
|
37.1
|
39.1
|
43.6
|
|
55.3
|
42.3
|
48.2
|
42.8
|
61.1
|
34.7
|
35.5
|
52.9
|
44.7
|
51.5
|