In the post office example, suppose that each full-time employee works 8 hours per day. Thus, Monday’s requirement of 17 workers can be viewed as a requirement of 8(17)  136 hours. The post office can meet its daily labor requirements by using both full-time and part-time employees. During each week, a fulltime employee works 8 hours a day for 5 consecutive days, and a part-time employee works 4 hours a day for 5 consecutive days. A full-time employee costs the post office $15 per hour, whereas a part-time employee (with reduced fringe benefits) costs the post office only $10 per hour. Union requirements limit part-time labor to 25% of weekly labor requirements.

a. Modify the model as necessary, and then use Solver to minimize the post office’s weekly labor costs.

b. Use SolverTable to determine how a change in the part-time labor limitation (currently 25%)

influences the optimal solution.

Skill-Extending Problems