Question: In a family there are 2 cars. The sum of the average miles per gallon obtained by the two cars in a particular week is 45. The first car has consumed 40 gallons during that week , and the second car has consumed 20 gallons , for a total of 1400 miles driven by the two cars combined. What was the average gas mileage obtained by each of the second car that week?
Answer: 20