Assignment
Description:
1. Suppose the Environmental Protection Agency (EPA) would like to investigate the impact that octane has on gas mileage. The following table shows the gas mileage for six cars that were driven 1,000 miles with three different grades of gasoline: 87, 89, and 93 octane. The gas mileage was recorded for each octane level. Each car was tested with all three gasoline grades. The results are shown in the following table.
Car 87 Octane 89 Octane 93 Octane
Maxima 22.6 23.3 23.0
Focus 28.0 31.0 30.1
Accord 21.5 23.0 22.5
Sonata 27.5 29.1 28.5
Camry 24.1 27.7 26.0
Jetta 30.0 32.0 30.7
a. Identify the factor.
b. List the levels of the factor.
c. List the blocks.
d. Identify the response variable.
e. Check the assumptions and explain your findings.
f. Identify the set of null and alternative hypotheses to be examined.
g. Using a level of significance of 5%, does the octane level appear to have an effect on the gas mileage?