Statistics homework quiz Due in 1hr quick response only

1. Use the given degree of confidence and sample data to construct a confidence interval for the population proportion p.

n = 195, x = 162; 95% confidence

Select one:

a. 0.788 < p < 0.873

b. 0.789 < p < 0.873

c. 0.778 < p < 0.883

d. 0.777 < p < 0.884

2. Find the value of zα/2 that corresponds to a confidence level of 91%.

Select one:

a. 1.645

b. 1.75

c. 1.34

d. 1.70

3. Assume that a sample is used to estimate a population proportion p. Find the margin of error E that corresponds to the given statistics and confidence level. Round the margin of error to four decimal places.

98% confidence; the sample size is 800, of which 40% are successes 

Select one:

a. 0.0404

b. 0.0339

c. 0.0446

d. 0.0355

4. 50 people are selected randomly from a certain population and it is found that 12 people in the sample are over 6 feet tall. What is the point estimate of the proportion of people in the population who are over 6 feet tall?

Select one:

a. 0.24

b. 0.18

c. 0.50

d. 0.76

5. Thirty randomly selected students took the calculus final. If the sample mean was 95 and the standard deviation was 6.6, construct a 99% confidence interval for the mean score of all students.

Select one:

a. 91.69 < μ < 98.31

b. 92.03 < μ < 97.97

c. 92.95 < μ < 97.05

d. 91.68 < μ < 98.32

6. Use the given data to find the minimum sample size required to estimate the population proportion. Margin of error: 0.028; confidence level: 99%;  and  unknown

Select one:

a. 2223

b. 1116

c. 1939

d. 2115

7. Find the appropriate critical value for the following:

 99% confidence level ; n = 17; σ is unknown; population appears to be normally distributed.

Select one:

a. zα/2 = 2.583

b. zα/2 = 2.567

c. tα/2 = 2.898

d. tα/2 = 2.921

8. Find the critical value χ2R corresponding to a sample size of 19 and a confidence level of 99 percent if the test it two-tailed.

Select one:

a. 6.265

b. 37.156

c. 34.805

d. 7.015

9. Find the critical value χ 2L corresponding to a sample size of 19 and a confidence level of 99 percent if the test is two-tailed.

Select one:

a. 6.265

b. 34.805

c. 7.015

d. 37.156

10. To find the standard deviation of the diameter of wooden dowels, the manufacturer measures 19 randomly selected dowels and finds the standard deviation of the sample to be s = 0.16. Find the 95% confidence interval for the population standard deviation σ.

Select one:

a. 0.12 < σ < 0.24

b. 0.15 < σ < 0.21

c. 0.11 < σ < 0.25

d. 0.13 < σ < 0.22