Painters are often paid either by the hour or on a per job basis. The rate they receive can affect their working speed. Suppose, they can work either for either $15 per hour, or for $560 plus $3 for each hour less than 40 if they can complete the job in less than 40 hours. Also suppose that it takes t hours to complete the job. Clearly, the hourly rate is better if t 40. If t < 40, for what values of t is the hourly rate the better pay scale?