A Fleet of Rental Cars - All the Same Make $24.1$

Multiple Choice

A fleet of rental cars - all the same make, model, and year - has a mean fuel efficiency of $24.1$ miles per gallon (mpg) . A random sample of 40 cars are selected and the air filter of each is replaced with a new one. Let $\mu$ be the population mean fuel efficiency score that would occur if every car's air filter were replaced. The air filter change is deemed effective if $\mu > 24.1 \mathrm { mpg }$ . A test is made of $H _ { 0 } : \mu = 24.1$ versus $H _ { 1 } : \mu > 24.1$ .

Assume that the air filter changes are effective. Which type of error is impossible?

A) Type I
B) Type II