Answer Happy

Gas Mileage The cost of fuel is a large component of the cost of ownership for most vehicles. Fuel cost is (almost) inversely proportional to gas mileage. Higher gas mileage means lower fuel cost and vice-versa. If you keep track of the number of miles driven on each tank of gas as well as how much gas is purchased, it is easy to calculate gas mileage. Many cell phone apps exist to track this. The data on the second page is the gas mileage for one of Jane Doe's cars taken over the past year. Use this sample of data to complete the following list. 1. Find the average fuel economy and the standard deviation for this sample. (10 pts.) 2. Find the 5-number summary (do not round). Construct a box-and-whiskers plot of this data. Does it show any skew or symmetry? If yes, which? Are there any outliers? If so, what are they? (12 pts.) 3. Set up a 95% Confidence Interval (round to 2 decimal places) to estimate the average fuel economy of the vehicle. (8 pts.) D. The manufacturer (by way of the EPA) prints city, highway, and combined fuel economy on the window sticker of each new car. Find the combined fuel economy rating for the vehicle (you may find the website fueleconomy.gov to be helpful here). From the point of view of Jane Doe's credit card bill, getting less than the specified gas mileage would be troublesome and annoying. Based on that information, determine the null and alternative hypotheses. Would this be a one-tailed hypothesis test or a two-tailed test? (6 pts.) E. Test whether Jane Doe is getting ripped off at the a = 0.05 level of significance. Show all the steps. Is she getting the claimed fuel economy? Does your confidence interval support your hypothesis test result? Why or why not? Discuss reasons why the measured fuel economy may be different from the manufacturer's claim. (14 pts.) This is due on Tuesday, May 3, by 10:00 p.m. Vehicle Information: 2016 Buick Regal (not eAssist), 2.4L, 4 cylinder, automatic (56) 24.86 20.95 23.78 25.21 21.15 21.44 21.13 23.28 22.07 23.72 21.35 24.73 21.18 23.15 19.96 21.87 22.52 20.76 21.13 22.14 23.84 20.14 24.39 18.75 21.25