Aschool typically sells 500 year books in a year for $50 each. the economics class does a project and discovers that they can sell 125 more year books for every $5 decrease in price. the revenue for year book sales is r(x)= ( 500 +125x )( 50- 5x )

to maximize the profit what price should the school charge for the yearbooks?

35, 40, 45, 50?