A car traveled 560 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?  Choose the correct answer
A) 9 B) 16 C) 21 D) 22 E) 27
Let the speed in highway be h mpg and in city be c mpg.   h = c+6   h miles are covered in 1 gallon   462 miles will be covered in 462/h.   Similarly c miles are covered in 1 gallon   336 miles will be covered in 336/c.   Both should be same (as car's fuel capacity does not change with speed)   =&gt; 336/c = 560/h   =&gt; 336/c = 560/(c+6)   =&gt; 336c+336*6=560c   =&gt;c=336*6/224= 
<gadget id="calculator">336*6/224</gadget>
<output>9</output>
9   9nswer 9.
<result>A</result>
A car traveled 560 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?