Question

1 - A 95% confidence interval for a population proportion was constructed using a sample proportion from a random sample. Which of the following statements are correct? Select all that apply.

A) We don't know if the 95% confidence interval actually does or doesn't contain the population proportion.

B) The population proportion must lie in the 95% confidence interval.

C) There is a 95% chance that the 95% confidence interval actually contains the population proportion.

D) The sample proportion must lie in the 95% confidence interval.

E) If we were to use a 90% confidence level, the confidence interval from the same data would produce an interval wider than the 95% confidence interval.

2 - Public Policy Polling recently conducted a survey asking adults across the U.S. about music preferences. When asked, 83 of the 574 participants admitted that they have illegally downloaded music.
* Create a 99% confidence interval for the true proportion of American adults who have illegally downloaded music. (Round your answers to two decimal places.)

( _____ , _____ )

You may need to use the appropriate Appendix Table to answer this question.

* Which of the following statement is true about the confidence interval in part (a)?

A) This confidence interval contains the true population proportion.

B) The sample proportion may or may not be in this confidence interval.

C) There is a 99% chance that the true population proportion lies in this confidence interval.

D) This confidence interval may not contain the true population proportion.

Answer 1