Introduction to Management Science 12th Edition by Bernard Taylor

تمرين 31

WeeMow Lawn Service provides lawn service, including mowing lawns and lawn care, landscaping, and lawn maintenance, to residential and commercial customers in the Draper town community. In the summer WeeMow has three teams that it schedules daily for jobs. Team 1 has five members, team 2 has four members, and team 3 has three members. On a normal summer day WeeMow will have approximately 14 jobs. Each team works 10 hours a day, but because of the heat plus work breaks, each team actually works only 45 minutes out of every hour. The following table shows the times (in minutes) and costs (in dollars) required for each team to complete the 14 jobs for a specific day.
The WeeMow manager wants to develop a schedule of team assignments to the jobs for this day. Formulate and solve a linear programming model to determine the assignments of teams to jobs that will minimize total job time the day, given a daily budget of $1,000. Indicate how many minutes each crew will work during the day. Next, reformulate and solve this model if cost minimization is the objective. Of these two models, which one do you think the manger should select and why