A car traveled 462 miles per tankful of gasoline on the highway and 336 miles per tankful of gasoline in the city. If the car traveled 9 fewer miles per gallon in the city than on the highway, how many miles per gallon did the car travel in the city? Choose one: A) 14 B) 16 C) 21 D) 24 E) 27

Rationale: "i treat such problems as work ones . work = rate * time mileage ( m ) = rate ( mpg ) * gallons ( g ) x gallons is a full tank { 462 = rx { 336 = ( r - 9 ) x solve for r , r = 33 33 - 9 = 24 mpg d"
Answer: D