An individual claims that the fuel consumption of his automobile does not depend on how fast the car is driven. To test the plausibility of this hypothesis, the car was tested at various speeds between 45 and 70 miles per hour. The miles per gallon attained at each of these speeds was determined, with the following data resulting:
|
Speed
|
Miles per Gallon
|
|
45
|
24.2
|
|
50
|
25.0
|
|
55
|
23.3
|
|
60
|
22.0
|
|
65
|
21.5
|
|
70
|
20.6
|
|
75
|
19.8
|
Do these data refute the claim that the mileage per gallon of gas is unaffected by the speed at which the car is being driven?