We have data on the city and highway fuel efficiency of 633 cars and trucks.

a) Would it be appropriate to use paired t methods to compare the city fuel efficiency of the cars and the trucks?
b) Would it be appropriate to use paired t methods to compare the city and highway fuel efficiencies of these vehicles?
c) A histogram of the differences (highway – city) is shown. Are the conditions for inference satisfied?

Transcribed Image Text:

Frequency of Difference 220 180 140 100 60 20 + -30 -20 -10 0 Difference 10 20