A manufacturing firm has discontinued production of a certain unprofitable product line. Considerate excess production capacity was created as a result. Management is considering devoting this excess capacity to one or more of three products: X1, X2 and X3. Machine hours required per unit are Machine Type Product X1 X2 X3 Milling Machine 8 2 3 Lathe 4 3 0 Grinder 2 0 1 The available time in machine hours per week is Machine Hours per Week Milling Machines 800 Lathes 480 Grinders 320 The sales people estimate they can sell all the units of X1 and X2 that can be made. But the sales potential of X3 is 80 units per week. Unit profits for X1, X2 and X3 are $20, $6, $8 respectively. If we define the decision variables as X1,X2, X3 --- the production quantities of the three products, the object function is to maxmize . In addition to non-negative constraints, other constraints are