1. Refer to the Real Estate data, which report information on homes sold in the Goodyear, Arizona, area during the last year.
a. Develop a 95% confidence interval for the mean selling price of the homes.
b. Develop a 95% confidence interval for the mean distance the home is from the center of the city.
c. Develop a 95% confidence interval for the proportion of homes with an attached garage.
d. To report your findings, write a business style memo to Gary Loftus, the president of the Goodyear Chamber of Commerce.
2. As a condition of employment, Fashion Industries applicants must pass a drug test. Of the last 215 applicants, 16 failed the test. (Use Student's z Distribution Table.)
a. Develop a 99% confidence interval for the proportion of applicants that fail the test. (Round your answers to 3 decimal places.)
For the applicants the confidence interval is between and .
b. Would it be reasonable to conclude that more than 11% of the applicants fail the test?
No
Yes
3. A random sample of 24 people employed by the Florida state authority established they earned an average wage (including benefits) of $65.00 per hour. The sample standard deviation was $5.72 per hour. (UseStudent's z Distribution Table.)
a. What is the best estimate of the population mean?
Estimated population mean $
b. Develop a 90% confidence interval for the population mean wage (including benefits) for these employees. (Round your answers to 2 decimal places.)
Confidence interval for the population mean wage is between and .
c. How large a sample is needed to assess the population mean with an allowable error of $1.00 at 98% confidence? (Round up your answer to the next whole number.)
Sample size