A dealer wishes to purchase a number of fans and sweing machines. He has only Rs. 5760 to invest and has space atmost for 20 items. A fan costs him Rs. 360 and a sewing machine Rs. 240. His expectation is that he can sell a fan at a profit of Rs. 22 and a sweing machine at a profit of Rs. 18. Assuming that he can sell all the items that he can buy, how should he linvest his money in order to maximise his profit? Formulate manufacturer produces three products, ordinary chairs.