Question

1. Do one of the following, as appropriate: (a) Find the critical value z_α/2, (b) find the critical value t_α/2, (c) state that neither the normal nor the t distribution applies.

90%; n = 10; σ is unknown; population appears to be normally distributed.

Group of answer choices

A. z_α/2 = 2.262

B. z_α/2 = 1.383

C. t_α/2 = 1.833

D. t_α/2 = 1.812

2. Find the margin of error.

95% confidence interval; n = 91 ;  = 53, s = 12.5

Group of answer choices

A. 4.80

B. 2.34

C. 2.23

D. 2.60

3. Use the given degree of confidence and sample data to construct a confidence interval for the population mean μ. Assume that the population has a normal distribution.

A laboratory tested twelve chicken eggs and found that the mean amount of cholesterol was 208 milligrams with s = 18.2 milligrams. Construct a 95 percent confidence interval for the true mean cholesterol content of all such eggs.

Group of answer choices

A. 196.5 < μ < 219.5

B. 196.3 < μ < 219.7

C. 196.4 < μ < 219.6

D. 198.6 < μ < 217.4

Solve the problem.

4. Find the critical value  corresponding to a sample size of 6 and a confidence level of 95 percent.

Group of answer choices

A. 0.831

B. 12.833

C. 11.07

D. 1.145

5. Use the given degree of confidence and sample data to find a confidence interval for the population standard deviation σ. Assume that the population has a normal distribution.

College students' annual earnings: 98% confidence; n = 9,  = $3194, s = $821

Group of answer choices

A. $646 < σ < $1071

B. $518 < σ < $1810

C. $499 < σ < $1607

D. $555 < σ < $1573

Answer 1