Enter the following information into an Excel
spreadsheet. The time estimates were made at the 90 percent level (see Section 5.2, Calculating Probabilistic Activity Times subsection). All activity times are in days.

Activity Predec. Opt. Normal Pess. LO6 a —56 9 b —44 6 c — 7 9 15 d a 66 6 e b 45 7 f b 12 16 17 g c 8 12 20 h c 7 9 16 i

d, e 10 14 18 j

f, g 6 12 20 k h 7 9 14

a. Draw the network. (You may use MSP, or draw an AOA or AON network by hand.)

b. Using Excel
, calculate the expected time (TE)
and variance for each activity.

c. Using the expected times, find the critical path and critical time. (Use the analytic method.)

d. Find the probability that the critical path will be completed in 38 days or less.

e. Are there any serious sources of merge bias? What are they? Calculate the probability of finishing the project on or before day 38 when merge bias is included.

f. Assume that the times in the table were made on the 99
percent level. Recalculate the activity variances with this assumption and find the probability that the critical path will be complete in 38 days.
(Note, the altered assumption will change activity variance, but not the expected activity durations.)
Briefly explain the difference in probabilities.
g. How many days are required for the critical path to have a .9 probability of completion?