SOLVED PROBLEM 3.4 To complete the wing assembly for an experimental aircraft, Jim Gilbert has laid out the seven major activities involved. These activities have been labeled A through G in the following table, which also shows their estimated completion times (in weeks) and immediate predecessors. Determine the expected time and variance for each activity. SOLUTION Expected times and variances can be computed using Equations (3-6) and (3-7) presented on page 78 in this chapter. The results are summarized in the following table: SOLVED PROBLEM 3.5 Referring to Solved Problem 3.4, now Jim Gilbert would like to determine the critical path for the entire wing assembly project as well as the expected completion time for the total project. In addition, he would like to determine the earliest and latest start and finish times for all activities. SOLUTION The AON network for Gilbert's project is shown in Figure 3.17. Note that this project has multiple activities (A and B) with no immediate predecessors, and multiple activities ( F and G ) with no successors. Hence, in addition to a unique starting activity (Start), we have included a unique finishing activity (End) for the project. Figure 3.17 shows the earliest and latest times for all activities. The results are also summarized in the following table: Figure 3.17 Critical Path for Solved Problem 3.5