11.14: Chapter Solution (Practice + Homework)
- Page ID
- 6140
1.
mean = 25 and standard deviation = 7.0711
3.
when the number of degrees of freedom is greater than 90
5.
\(df = 2\)
6.
a test of a single variance
8.
a left-tailed test
10.
\(H_0: \sigma^2 = 0.812\);
\(H_a: \sigma^2 > 0.812\).
12.
a test of a single variance
16.
a goodness-of-fit test
18.
3
20.
2.04
21.
We decline to reject the null hypothesis. There is not enough evidence to suggest that the observed test scores are significantly different from the expected test scores.
23.
\(H_0\): the distribution of AIDS cases follows the ethnicities of the general population of Santa Clara County.
25.
right-tailed
27.
2016.136
28.
- 30.
a test of independence
a test of independence
34.
8
36.
6.6
39.
Smoking level per day African American Native Hawaiian Latino Japanese Americans White Totals 1-10 9,886 2,745 12,831 8,378 7,650 41,490 11-20 6,514 3,062 4,932 10,680 9,877 35,065 21-30 1,671 1,419 1,406 4,715 6,062 15,273 31+ 759 788 800 2,305 3,970 8,622 Totals 18,830 8,014 19,969 26,078 27,559 10,0450 Table \(\PageIndex{54}\) 41.
Smoking level per day African American Native Hawaiian Latino Japanese Americans White 1-10 7777.57 3310.11 8248.02 10771.29 11383.01 11-20 6573.16 2797.52 6970.76 9103.29 9620.27 21-30 2863.02 1218.49 3036.20 3965.05 4190.23 31+ 1616.25 687.87 1714.01 2238.37 2365.49 Table \(\PageIndex{55}\) 43.
10,301.8
44.
right
46.
- 48.
test for homogeneity
test for homogeneity
52.
All values in the table must be greater than or equal to five.
54.
3
57.
a goodness-of-fit test
59.
a test for independence
61.
Answers will vary. Sample answer: Tests of independence and tests for homogeneity both calculate the test statistic the same way \(\sum_{(i j)} \frac{(O-E)^{2}}{E}\). In addition, all values must be greater than or equal to five.
63.
true
65.
false
67.
225
69.
\(H_0: \sigma^2 \leq 150\)
71.
36
72.
Check student’s solution.
74.
The claim is that the variance is no more than 150 minutes.
76.
a Student's \(t\)- or normal distribution
78.
- 48.