Question 1 Sample with size n 100 has mean 30 Assuming the

Question 1

Sample with size n = 100 has mean = 30.
Assuming the population standard deviation is 8,
construct 95% confidence interval for population mean.
Use formula on page 312, z_?/2 = 1.96  

between 28.4 and 31.6

between 27.0 and 33.0

between 26.1 and 34.2

between 24.1 and 35.9

1 points

Question 2

With sample mean x = 12.5, sample size n = 40
and population standard deviation = 4
find 99% confidence interval for population mean.
Use formula on page 312 with z_?/2 = 2.575

between 11.5 and 13.5

between 10.9 and 14.1

between 10.1 and 15.1

between 7.4 and 14.2

1 points

Question 3

Use Appendix Table IV to find t_0.10 for sample size n = 16.
Remember, df in the table is: df = n ? 1

2.015

1.860

1.725

1.341

1 points

Question 4

For sample mean x = 150, sample size n = 36
and sample standard deviation s = 40
find 80% confidence interval for population mean.
Population standard deviation is not known,
you should use formula on page 328 with t-value
from Appendix Table IV (use column t_0.10).

135.6 to 148.4

154.2 to 175.8

141.3 to 158.7

162.3 to 187.5

1 points

Question 5

Use example posted in this week Lectures section
to estimate Population Proportion.
Sample proportion is p_s = 0.48, sample size 125,
zc = 1.96 (90% confidence level).

0.26 to 0.64

0.39 to 0.57

0.41 to 0.52

0.28 to 0.71

Solution

1) between 28.4 and 31.6

2) b) between 10.9 and 14.1

3) 1.341

4) 141.3 to 158.7

5) 0.41 to 0.52