Question :
SkyEducation will develop a new branch in the city for J2EE programming training. The information is given in the following table.
(Ignore the crashing parameters.)
| Task |
a |
b |
c |
d |
e |
f |
g |
| Predecessors |
- |
- |
- |
a |
b |
c |
d,e |
| Normal time (ti weeks) |
2 |
3 |
4 |
7 |
6 |
15 |
10 |
| Crash time (ti') |
1 |
1 |
2 |
4 |
3 |
5 |
5 |
| Normal cost (ci) |
1000 |
2100 |
1500 |
500 |
900 |
800 |
1250 |
| Crash cost (ci') |
1200 |
2500 |
1600 |
800 |
1200 |
1300 |
1750 |
| Max crash (Mi) |
1 |
2 |
2 |
3 |
3 |
10 |
5 |
| Crash cost/weeks (ki) |
200 |
200 |
50 |
100 |
100 |
50 |
100 |
SkyEducation's plan is to open this new branch within 18 weeks.
a. Formulate a linear program to determine the minimum cost plan.
b. Build a spreadsheet model of the project. Use Solver to find the optimal solution. What's the minimum cost plan to crash the project?