Sixteen cars are first driven with a standard fuel and then with Petro coal, a gasoline with a methanol additive. The results of the nitrous oxide emissions (NOx) test are as follows:

a. How would you test the hypothesis that the two population standard deviations are the same?
b. Which test did you use? What are the assumptions underlying that test?

Transcribed Image Text:

Type of fue verage NO Standard deviation of NO Standard Petrocoal 1.075 1.159 0.5796 0.6134