Discussion:
Q: A research firm wants to compare the miles per gallon of unleaded regular, mid-grade, and super grades of gasoline. They drive the same car under approximately similar driving conditions and changing out the type of gasoline used. At the .05 significance level, is there a difference in gas mileage for the different types of gas? Write out your null and alternative hypotheses for the problem and state what the finding means practically.
Regular
Mid-Grade
Super
21
23
26
23
25
25
24
24
27
24
26
26
26
24
30
26
22
27
28
27
32