Have vehicles gotten more fuel-efficient over the years? Between 1960 and 1999 the size and shape of automobiles in the United States has changed almost annually. The amount of fuel consumed by these vehicles has also
changed. The following table describes the average fuel consumption per year per passenger car in gallons of
gasoline
1960
Year, t
Gallons Consumed Per
Passenger Car
1970
1760
1980 1990 1995
1576 520 530
1997 1998 1999
538 1544 552
668
Determine the average rate of change, in gallons of gas per year, from 1960 and 1999 and then determine what the
result means in this situation.
a. -0.33gal/year, the average fuel consumption per year of a passenger car in the U. S.
decreased by a third of a gallon per year.
b. 0.33 gallyear, the average fuel consumption per year of a passenger car in the U. S.
increased by a third of a gallon per year.
C. 2.97 gal/year, the average fuel consumption per year of a passenger car in the U. S.
increased by nearly 3 gal/year.
d -2.97 gal/year; the average fuel consumption per year of a passenger car in the U. S.