A Product Mix Problem with "Fixed Charge" Variables

Gandy cloth company can manufacture three kinds of clothing: shirts, shorts, and pants.  Making each kind of clothing requires renting a particular kind of machine, which has effectively unlimited capacity, but cannot be used for any other kind of clothing.  The following table describes the production process:

  Cost of
Machine
($/Week)
Labor Hours
Per Unit
Yards of
Cloth
Per Unit
Revenue
per Unit
Variable
Cost
per Unit
Shirts $200 3 4 $12 $6
Shorts $150 2 3 $8 $4
Pants $100 6 4 $15 $8

Gandy can obtain up to 150 hours of labor and 160 yards of cloth per week.  How can the firm maximize its profits?