MATH 318, Chapter 12 Quiz

Name:
You may use a calculator on this quiz. You may not use a cell phone or computer. Please show your work carefully and give justifications for your answers. If you find that you are spending a lot of time on one problem, leave it blank and move on to the next. There are questions on both sides of the page.
  1. (30 points) [Modified from #8, p.544] Draw a project network for the following activities and predecessors. (It's ok if your network flows down the side or back across the bottom of the page as long as the arrows linking nodes are correct.)

    ActivityPredecessor Time (weeks)SlackCritical?
    A-6  
    B-8  
    CA12  
    DA,B4  
    EC6  
    FD,E15  
    GE12  
    HF,G8  

     

     

     

     

     

     

     

     

     

     

     

     

     

  2. (20 points) Use the project network from the previous problem to compute the estimated completion time of the project.

     

     

  3. (20 points) Fill in the columns for slack and critical activities (yes/no) in the table in problem 1.

     

  4. (15 points) Suppose each of the critical activities for problem 1 has variance:

    ((b-a)/6)2 = 2 weeks2.

    Compute the standard deviation of the time for completion of the entire project.

     

     

     

     

     

     

  5. (15 points) The following completion time estimates were provided for an activity:

    Optimistic: 5
    Most Probable: 7
    Pessimistic: 12

    What is the expected completion time of the project?

     

Bonus (5 points) Suppose your budget allowed you to pay workers overtime to reduce the completion time of any one project in problem 1. Assuming no task time could be reduced to less than half its original estimate (so you can't reduce the time needed for task H below 4 weeks), what task would you shorten and by how much?