Question

In a recent poll of 200 households in the area. 122 households had two or more vehicles. Using a 99% level of confidence, estimate the true proportion of households in the area that have two or more vehicles.

What is the correct critical value to be used in calculating the interval estimate?

a. 1.645

b. 1.414

c. 2.575

d. 2.018

What is the 99% confidence interval estimate?

a. (0.521, 0.699)

b. (0.542, 0.678)

c. (0.553, 0.667)

d. (0.513, 0.707)

With the same survey data, if a 90% confidence level is used instead, the new interval estimate will be

a. wider than the 99% confidence interval estimate.

b. narrower than the 99% confidence interval estimate.

c. having the same width as the 99% confidence interval estimate.

d. Can’t decide.

What is the width of the 99% confidence interval estimate?

a. 0.089

b. 0.136

c. 0.178

d. 0.114

Answer 1