Studies show that gasoline use for the hybrid cars that are sold in the United States is normally distributed with a mean of 51.7 miles per gallon (mpg) for 2002. A random sample of 49 of the newer hybrid cars is tested in 2004 and found to have an average of 54.2 mph on the highway and a standard deviation of 4.5 mpg. Is this sufficient evidence to conclude that the mean mpg is higher in the newer cars? Test the appropriate hypothesis using alpha = 0.05. Use the traditional method approach.© BrainMass Inc. brainmass.com December 24, 2021, 4:56 pm ad1c9bdddf
Null Hypothesis: Ho: M =51.7 mpg
Alternative Hypothesis: H1: M > 51.7 mpg
This is a one tailed test since we are testing whether M > 51.7 mpg
If we were testing whether M not equal to 51.7 mpg we would have two tailed test ...
Tests the hypothesis that the mean mileage is higher in the newer cars.