Problema Solution
Car A has a gas tank that holds 20gallons of gas and car B holds 15 gallons. On a road trip 4,000 miles they used 140 gallons of gas, and they filled up the same amount of times. how many gallons did each vehicle use? What is the gas mileage of car A and car B?
Answer provided by our tutors
we assume that each car used exactly a full tank of gas between fillups and each car arrived with the gas tank on empty
we also assume that '140 gallons of gas' represents the combined amount of gas used by the two cars, therefore let 'a' represent the gallons used by car A and '140-a' represents the gallons used by car B
let 'x' represent the number of times the cars filled up, then car A used 20x gallons of gas and car B used 15x gallons of gas
miles per gallon = mpg
140 = 20x + 15x
solving for 'x' we have x=4
4*20 = 80
4*15 = 60
4000/80 = 50
4000/60 = 66.7
car A used 80 gallons of gas, car B used 60 gallons of gas
car A's gas mileage was 50 mpg, car B's gas mileage was approximately 66.7 mpg