Given: A contractor is planning a job that will require a large amount of gravel and sand. The estimates for the necessary gravel and sand are:
|
Coarse Gravel |
20,000 cu yds |
|
Fine gravel |
29,000 cu yds |
|
Sand |
20,000 cu yds |
There are two pits from which material can be obtained, and the plan is to haul from these two pits and to separate (screen) the material on the job, for whatever material is needed. Analysis shows that the material at each pit has the following composition:
|
Pit A |
Pit B |
|
|
Coarse Gravel |
20% |
30% |
|
Fine Gravel |
14% |
50% |
|
Sand |
25% |
20% |
|
Waste |
41% |
0% |
It costs $8/cu yd for material and hauling from pit A, and $18/cu yd from pit B.
Required: Solve this as a linear programming problem to minimize the delivered cost.