please help

A textbook company publishes computer, educational and uility type of books. Their business strategy is to market a tolal of 36 new books each year, at least four of these being games. The number of uiliy books

published is never more than twice the number of educational books. On average, the company makes an annual profit of $5000 on each computer book, $8000 on each educational book, and $6000 on each utility book. How many educational books should the company publish annually for maximum profit?