A manufacturer wants to maximize the profit of two products. Product X yields a profit of $ 2.50 per unit, and product Y yields a profit of $3.20 per unit. Market tests and available resources have indicated the following constraints: The combined production level should not exceed 1200 units per month. The demand for product Y is no more than half the demand for product X. The production level of product X is less than or equal to 600 units plus three times the production level of product Y.