Vince runs 2 miles a day, 5 days a week. Vince wants to run a marathon, so
he asked the coach for some advice.
She tells him he needs to work up to running at least 40 miles per week. He
should run that distance for at least 6 weeks before the marathon. She also
advises him not to increase his mileage more than 10% every 2 weeks. If Vince follows this advise, what is the shortest amount of time that will pass before he can enter the marathon?