单选题
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 6 fewer miles per gallon in the city than on the highway，how many miles per gallon did the car travel in the city?
【正确答案】
B
【答案解析】Let g be the number of gallons of gasoline in1 tankful. Then the number of miles per gallon while traveling on the highway is 462/g and this number is 6 more than 336/g，which is the number of miles per gallon while traveling in the city.Solving462/g= 6 +336/g gives g = 21. Therefore, the number of miles per gallon while the car was traveling in the city was336/21= 16.The correct answer is B.