Question: Suppose you drive a 2013 model automobile that averages 25miles per gallon (mpg) for 15,000 miles annually. If you purchase a new automobile that averages 30 mpg, how much extra money can you afford, based on fuel savings, to invest in the new car? Your personal interest rate is 6% per year, and you keep the new automobile for 5 years. Gasoline costs $4.00 per gallon.