Obbo Tola employs two part-time typists, Chaltu and Roba, for his typing needs. Chaltu charges $15 an hour and can type 6 pages an hour, while Roba charges $18 an hour and can type 8 pages per hour. Each typist must be employed at least 8 hours per week to keep them on the payroll. If Mr. Tola has at least 208 pages to be typed, how many hours per week should he employ each typist to minimize his typing costs, and what will be the total cost?