Question

Five hundred eleven (511) homes in a certain southern California community are randomly surveyed to determine if they meet minimal earthquake preparedness recommendations. One hundred seventy-three (173) of the homes surveyed met the minimum recommendations for earthquake preparedness and 338 did not.


1) Find the confidence interval at the 90% Confidence Level for the true population proportion of southern California community homes meeting at least the minimum recommendations for earthquake preparedness.

(  ,  )
(Round to the 4th decimal place)

2) State the previous confidence interval in the form of p^±ME.
±
(Round to the 5th decimal place)

3) Five hundred eleven (511) homes in a certain southern California community are randomly surveyed to determine if they meet minimal earthquake preparedness recommendations. One hundred seventy-three (173) of the homes surveyed met the minimum recommendations for earthquake preparedness and 338 did not.

The point estimate for the population proportion of homes that do not meet the minimum recommendations for earthquake preparedness is .

(Round to the 4th decimal place)

4) What is meant by the term “90% confident” when constructing a confidence interval for a proportion?

• A. If we took repeated samples, approximately 90% of the samples would produce the same confidence interval.
• B. If we took repeated samples, approximately 90% of the confidence intervals calculated from those samples would contain the sample proportion.
• C. If we took repeated samples, approximately 90% of the confidence intervals calculated from those samples would contain the true value of the population proportion.
• D. If we took repeated samples, the sample proportion would equal the population mean in approximately 90% of the samples.

Answer 1