Please show me how to answer this without excel and by hand please.

A company manufactures two products, A and B, on two machines, I and II. It has been determined that the company will realize a profit of $3/unit on product A and a profit of $4/unit on product B. To manufacture 1 unit of product A requires 6 min on machine I and 5 min on machine II. To manufacture 1 unit of product B requires 9 min on Machine I and 4 in on machine II. There are 5hr of machine time available on machine I and 3 hr of machine time available on machine II in each work shift. How many units of each product should be produced in each shift to maximize the Companys profit? What is the largest profit the company can realize? Is there any time left unused on the machines?