Deck 13: Project Scheduling: Pertcpm

Question 1

For an activity with more than one immediate successor activity,its latest-finish time is equal to the

A)largest latest-finish time among its immediate successors.
B)smallest latest-finish time among its immediate successors.
C)largest latest-start time among its immediate successors.
D)smallest latest-start time among its immediate successors.

Answer 1

D

Question 2

PERT and CPM are applicable only when there is no dependence among activities.

Answer 2

False

Question 3

The critical path

A)is any path that goes from the starting node to the completion node.
B)is a combination of all paths.
C)is the shortest path.
D)is the longest path.

Answer 3

D

Question 4

Activities with zero slack

A)can be delayed.
B)must be completed first.
C)lie on a critical path.
D)have no predecessors.

Question 5

To determine how to crash activity times

A)normal activity costs and costs under maximum crashing must be known.
B)shortest times with crashing must be known.
C)realize that new paths may become critical.
D)All of the alternatives are true.

Question 6

For an activity with more than one immediate predecessor activity,which of the following is used to compute its earliest finish (EF)time?

A)the largest EF among the immediate predecessors.
B)the average EF among the immediate predecessors.
C)the largest LF among the immediate predecessors.
D)the difference in EF among the immediate predecessors.

Question 7

Activities K,M and S immediately follow activity H,and their latest start times are 14,18,and 11.The latest finish time for activity H

A)is 11.
B)is 14.
C)is 18.
D)cannot be determined.

Question 8

Activities G,P,and R are the immediate predecessors for activity W.If the earliest finish times for the three are 12,15,and 10,then the earliest start time for W

A)is 10.
B)is 12.
C)is 15.
D)cannot be determined.

Question 9

PERT and CPM

A)are most valuable when a small number of activities must be scheduled.
B)have different features and are not applied to the same situation.
C)do not require a chronological relationship among activities.
D)have been combined to develop a procedure that uses the best of each.

Question 10

When activity times are uncertain,

A)assume they are normally distributed.
B)calculate the expected time,using (a + 4m + b)/6.
C)use the most likely time.
D)calculate the expected time,using (a + m + b)/3.

Question 11

Which is not a significant challenge of project scheduling?

A)deadlines exist.
B)activities are independent.
C)many employees could be required.
D)delays are costly.

Question 12

In deciding which activities to crash,one must

A)crash all critical activities.
B)crash largest-duration activities.
C)crash lowest-cost activities.
D)crash activities on the critical path(s)only.

Question 13

Which of the following is a general rule for crashing activities?

A)Crash only non-critical activities.
B)Crash activities with zero slack.
C)Crash activities with the greatest number of predecessors.
D)Crash the path with the fewest activities.

Question 14

Activities following a node

A)can begin as soon as any activity preceding the node has been completed.
B)have an earliest start time equal to the largest of the earliest finish times for all activities entering the node.
C)have a latest start time equal to the largest of the earliest finish times for all activities entering the node.
D)None of the alternatives is correct.

Question 15

The earliest start time rule

A)compares the starting times of all activities for successors of an activity.
B)compares the finish times for all immediate predecessors of an activity.
C)determines when the project can begin.
D)determines when the project must begin.

Question 16

Critical activities are those that can be delayed without delaying the entire project.

Question 17

A path through a project network must reach every node.

Question 18

Which of the following is always true about a critical activity?

A)LS = EF.
B)LF = LS.
C)ES = LS.
D)EF = ES.

Question 19

Slack equals

A)LF - EF.
B)EF - LF.
C)EF - LS.
D)LF - ES.

Question 20

Arcs in a project network indicate

A)completion times.
B)precedence relationships.
C)activities.
D)the critical path.

Question 21

When activity times are uncertain,an activity's most likely time is the same as its expected time.

Question 22

Constraints in the LP models for crashing decisions are required to compare the activity's earliest finish time with the earliest finish time of each predecessor.

Question 23

It is possible to have more than one critical path at a time.

Question 24

The variance in the project completion time is the sum of the variances of all activities in the project.

Question 25

When activity times are uncertain,total project time is normally distributed with mean equal to the sum of the means of all of the critical activities.

Question 26

A critical activity can be part of a noncritical path.

Question 27

Crashing refers to an unanticipated delay in a critical path activity that causes the total time to exceed its limit.

Question 28

The length of time an activity can be delayed without affecting the project completion time is the slack.

Question 29

Consider the following PERT/CPM network with estimated times in weeks.The project is scheduled to begin on May 1. The three-time estimate approach was used to calculate the expected times and the following table gives the variance for each activity:

a.Give the expected project completion date and the critical path.
b.By what date are you 99% sure the project will be completed?

Question 30

All activities on a critical path have zero slack time.

Question 31

A project consists of five activities.Naturally the paint mixing precedes the painting activities.Also,both ceiling painting and floor sanding must be done prior to floor buffing.

a.Construct the PERT/CPM network for this problem.
b.What is the expected completion time of this project?
c.What is the probability that the project can be completed within 9 hr.?

Question 32

Consider a project that has been modeled as follows:

a.Draw the PERT/CPM network for this project and determine project's expected completion time and its critical path.
b.Can activities E and G be performed simultaneously without delaying the minimum project completion time?
c.Can one person perform A,G,and I without delaying the project?
d.By how much can activities G and L be delayed without delaying the entire project?
e.How much would the project be delayed if activity G was delayed by 7 hours and activity L was delayed by 4 hours? Explain.

Question 33

The earliest start time for an activity is equal to the smallest of the earliest finish times for all its immediate predecessors.

Question 34

The earliest finish time for the final activity is the project duration.

Question 35

The project manager should monitor the progress of any activity with a large time variance even if the expected time does not identify the activity as a critical activity.

Question 36

The difference between an activity's earliest finish time and latest finish time equals the difference between its earliest start time and latest start time.

Question 37

The latest finish time for an activity is the largest of the latest start times for all activities that immediately follow the activity.

Question 38

For the project represented below,determine the earliest and latest start and finish times for each activity as well as the expected overall completion time.

Question 39

The critical path for this network is A - E - F and the project completion time is 22 weeks.
If a deadline of 17 weeks is imposed,give the linear programming model for the crashing decision.

Question 40

The linear programming model for crashing presented in the textbook assumes that any portion of the activity crash time can be achieved for a corresponding portion of the activity crashing cost.

Question 41

Joseph King has ambitions to be mayor of Williston,North Dakota.Joe has determined the breakdown of the steps to the nomination and has estimated normal and crash costs and times for the campaign as follows (times are in weeks).
Joe King is not a wealthy man and would like to organize a 16-week campaign at minimum cost.Write and solve a linear program to accomplish this task.