In: Statistics and Probability
Fuel Efficiency of Manual and Automatic Cars
Each year the US Environmental Protection Agency (EPA) releases fuel economy data on cars manufactured in that year. Below are summary statistics on fuel efficiency (in miles/gallon) from random samples of cars with manual and automatic transmissions manufactured in 2012. Do these data provide strong evidence of a difference between the average fuel efficiency of cars with manual and automatic transmissions in terms of their average city mileage? Assume that conditions for inference are satisfied.
City MPG, Automatic | City MPG, Manual | |
---|---|---|
Mean | 16.12 | 19.85 |
SD | 3.58 | 4.51 |
n | 26 | 26 |
The hypotheses for this test are:
The test statistic is: (please round to two decimal
places)
The p-value is: (please round to four decimal
places)
Interpret the result of the hypothesis test in the context of the
problem: