An expert who works for a car magazine obtained random data (rounded to the nearest thousand) among two categories of used or new cars:

Domestic
Foreign

The expert would like to understand sales based on list price (rounded to the nearest thousand dollars), sale price (rounded to the nearest thousand dollars), and number of days it takes to sell each car. The complete data set is in the file named Cars.

Managerial Report

Prepare a report (see below) that summarizes your assessment of the nature of the car market. Be sure to include the following seven items in your report.

1 Descriptive statistics (mean, median, range, standard deviation, and coefficient of variation) to summarize each of the three variables for the all Domestic cars. Use z-scores to determine if there any outliers in the data set for any of the three variables. If there are any outliers in any category, please list them and state for which category they are an outlier. If a result is an outlier, state whether it is below or above the mean.

2 Descriptive statistics (mean, median, range, standard deviation, and coefficient of variation) to summarize each of the three variables for the all Foreign cars. Use z-scores to determine if there any outliers in the data set for any of the three variables. If there are any outliers in any category, please list them and state for which category they are an outlier. If a result is an outlier, state whether it is below or above the mean.

3 Compare your summary results from #1 and #2. Discuss any specific statistical results that would help the car expert understand the car market.

4 Develop a 98% confidence interval estimate of the population mean sales price and population mean number of days to sell for Domestic cars. What is the Margin of error? What are the lower (or left) and upper (or right) endpoints of the confidence interval? Interpret your results.

5 Develop a 98% confidence interval estimate of the population mean sales price and population mean number of days to sell for Foreign cars. What is the Margin of error? What are the lower (or left) and upper (or right) endpoints of the confidence interval? Interpret your results.

6 Assume the car expert requested estimates of the mean number of days to sell for the Domestic cars with a margin of error of seven days and the mean number of days of Foreign cars with a margin of error of eight days. Using 98% confidence, how large should the sample sizes be for each?

7 Suppose a Domestic car has a list price of $30,000 and a Foreign car has a list price of $30,000. What is your estimate of the final selling price (based on the percent difference for the sale and list price) and number of days required to sell each of these cars?