When automobile companies advertise gasoline consumption of particular model, they provide the average miles per gallon for that model. Standards require that the estimate should be in plus or minus 1/2 miles of the true average, with the 99% confidence level. A new model called the Shark is being marketed, and the advertising director needs to know what average miles per gallon to employ in this advertisements. Prototype testing points out the Shark typically gets between 13 and 29 miles per gallon. How large of the sample of Sharks should be employed in order to obtain the average miles per gallon to be employed in the advertisements? Note: The standard deviation (?) can be estimated as the range divided by 4
a. Determine the numerical value of Z?
b. Determine the estimated standard deviation?
c. Determine the value of E?
d. Determine the value of the sample size n?