What hypothesis testing procedure should you use to answer these questions? Assume all samples are simple random samples, and assume α = 0.05 if it isn’t specified.
A car company says that the mean gas mileage for its luxury sedan is at least 21 mpg. You believe the claim is incorrect and find that a random sample of 5 cars has a mean gas mileage of 19 mpg and a sample standard deviation of 4 mpg. Assume the gas mileage of all of the company’s luxury sedans is normally distributed. At α = 0.05, test the company’s claim.
Question 20 options:
One sample z-test for the population mean.
Two sample z-test for the population means.
One sample z-test for proportions.
Two sample z-test for proportions.
One sample t-test for the population mean.
None of our hypothesis tests fit.