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There are 2 parts to this answer, I provided the data attached that is needed for both. To complete this scenario, use the Confidence Interval Calculator and the Area Gas Prices document. The newspaper has decided to write an article about gasoline prices in the Twin Cities area (Minneapolis and St. Paul, Minnesota). The has designed a survey and taken a simple random sample of regular unleaded gas prices at 70 area stations. The results are in the Area Gas Prices file (in Updates and Handouts). The ‘s policy is that no data will be reported unless they are 95 percent confident that the numbers are correct. As the new manager of the data verification unit at the , you need to develop a 95 percent confidence interval for the average price of regular unleaded gasoline in the Twin Cities metro area. You already know how to compute sample parameters like the sample mean and sample standard deviation; this scenario simply asks y

ou to complete a confidence interval for the data provided above and communicate the results to the ‘s business manager. To complete this scenario, use the Sample Size Estimator file provided in Resources. The third shift at the Microsoft’s Windows security unit in Redmond, Washington is considering replacing its coffee brewing units with new German-made brewers. As the newest member of this elite Microsoft team, you have been assigned to investigate this proposal. Develop a 99 percent confidence interval for the average yield (cups per pound) for the new German coffee brewer. The margin of error should be no bigger than .3 (three tenths of a cup). Based on experience with the current coffee makers, your best guess for the population standard deviation, sigma, is 1.2 cups. How big of a sample do you need? Calculate the estimated sample size needed for the above scenario and communicate your findings to the business manager.