Engineers are testing company fleet vehicle fuel economy (miles per gallon) performance by using different types of fuel. one vehicle of each size is tested. does this sample provide sufficient evidence to conclude that there is a significant difference in treatment means?
87 octane 89 octane 91 octane ethanol 5% ethanol 10% compact 31.
2 31.6 22.0 29.7 30.6
mid-size 17.3 17.6 18.9 17.2 28.2
full-size 27.2 28.1 15.9 31.9 29.7
suv 20.0 22.0 20.7 23.6 31.4