Question 1

From this PERT/CPM network,determine the list of activities and their predecessors.

Accepted Answer

$$\begin{array}{l}
\quad\quad\quad\quad\quad\quad\text { Immediate }\
\begin{array} { c c } 
\text { Activity } & \text { Predecessor } \
\hline \text { A } & \cdots \
\text { B } & \cdots \
\text { C } & \text { A } \
\text { D } & \text { A B } \
\text { E } & \text { C, D } \
\text { F } & \text { D } \
\text { G } & \text { E } \
\text { H } & \text { F, G }
\end{array}
\end{array}$$

Question 2

Once the earliest and latest times are calculated,how is the critical path determined?

Accepted Answer

The critical path in project management refers to the sequence of stages determining the minimum time needed to complete a project. Once the earliest start (ES) and latest finish (LF) times for each task are calculated, the critical path can be determined by following these steps:

1. **Identify Dependencies**: List all the tasks required to complete the project and identify the dependencies between tasks. This means understanding which tasks must be completed before others can start.

2. **Calculate Duration**: For each task, calculate the duration it will take to complete. This is typically given or estimated during the planning phase.

3. **Determine Earliest Start (ES) and Earliest Finish (EF) Times**: Using the forward pass method, calculate the ES and EF for each task. The ES for the first task is typically zero, and the EF is its duration. For subsequent tasks, the ES is the maximum EF of all its predecessor tasks, and the EF is the ES plus the task duration.

4. **Determine Latest Finish (LF) and Latest Start (LS) Times**: Using the backward pass method, calculate the LF and LS for each task. The LF for the final task is its EF. For preceding tasks, the LF is the minimum LS of all its successor tasks, and the LS is the LF minus the task duration.

5. **Calculate Slack or Float**: For each task, calculate the slack or float by subtracting the ES from the LS or the EF from the LF. Slack is the amount of time that a task can be delayed without affecting the project completion date.

6. **Identify the Critical Path**: The critical path is the sequence of tasks that have zero slack. These tasks cannot be delayed without affecting the project's completion date. To identify the critical path, look for the longest path through the network diagram or the path with tasks where the ES equals the LS and the EF equals the LF.

7. **Verify the Critical Path**: Double-check the calculations and the sequence of tasks to ensure that the identified path is indeed the longest path with no slack.

8. **Monitor and Update**: Throughout the project execution, monitor the critical path tasks closely as any delay in these tasks will directly impact the project completion date. Update the critical path as necessary when changes occur in the project's execution.

By following these steps, project managers can determine the critical path and focus their resources and attention on the tasks that are most critical to the project's timely completion.

Question 3

All activities on a critical path have zero slack time.

Accepted Answer

A) True 
 B)False  True

Question 4

Given the following network with activities and times estimated in days,   $$\begin{array}{l}
\quad\quad\quad\quad\quad\quad\quad\quad\quad\quad\quad\quad\text { Most }\
\begin{array} { c c c c } 
\text { Activity } & \text { Optimistic } & \text { Probable } & \text { Pessimistic } \
\hline \text { A } & 2 & 5 & 6 \
\text { B } & 1 & 3 & 7 \
\text { C } & 6 & 7 & 10 \
\text { D } & 5 & 12 & 14 \
\text { E } & 3 & 4 & 5 \
\text { F } & 8 & 9 & 12 \
\text { G } & 4 & 6 & 8 \
\text { H } & 3 & 6 & 8 \
\text { I } & 5 & 7 & 12 \
\text { J } & 12 & 13 & 14 \
\text { K } & 1 & 3 & 4
\end{array}
\end{array}$$ 
a.What are the critical path activities?
b.What is the expected time to complete the project?
c.What is the probability the project will take more than 28 days to complete?

Accepted Answer

@#IMG-DLM& @#IMG-DLM& CRITICAL PATH: C-H-J-K
EXPECTED PROJEC

Question 5

Explain how and why all predecessor activities must be considered when finding the earliest start time.

Accepted Answer

When finding the earliest start time for

Question 6

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

Accepted Answer

A) True 
 B)False

Question 7

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.

Accepted Answer

A) True 
 B)False

Question 8

A critical activity is:

Accepted Answer

A) an activity that consumes no time but shows precedence between events 
B) a milestone accomplishment within the project 
C) an activity with zero slack 
D) the beginning of an event 
A) an activity that consumes no time but shows precedence between events 
B) a milestone accomplishment within the project 
C) an activity with zero slack 
D) the beginning of an event

Question 9

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

Accepted Answer

A) True 
 B)False

Question 10

The earliest start time rule

Accepted Answer

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. 
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 11

Why should projects be monitored after the critical path is found?

Accepted Answer

Projects should be monitored after the c

Question 12

The normal distribution tends to be a better approximation of the distribution of total time for shorter projects where the critical path has relatively few activities.

Accepted Answer

A) True 
 B)False

Question 13

Which is not a significant challenge of project scheduling?

Accepted Answer

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

Question 14

The critical path

Accepted Answer

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. 
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.

Question 15

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

Accepted Answer

A) True 
 B)False

Question 16

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

Accepted Answer

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. 
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 17

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

Accepted Answer

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

Question 18

To determine how to crash activity times

Accepted Answer

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. 
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 19

The critical path for this network is A - E - F and the project completion time is 22 weeks.   $$\begin{array} { c c c c r } 
\text { Activity } & \begin{array} { c } 
\text { Normal } \
\text { Time }
\end{array} & \begin{array} { c } 
\text { Crash } \
\text { Time }
\end{array} & \begin{array} { c } 
\text { Normal } \
\text { Cost }
\end{array} & \begin{array} { c } 
\text { Crash } \
\text { Cost }
\end{array} \
\hline \text { A } & 12 & 8 & 8,000 & 12,000 \
\text { B } & 14 & 10 & 5,000 & 7,500 \
\text { C } & 8 & 8 & 10,000 & 10,000 \
\text { D } & 5 & 3 & 6,000 & 8,000 \
\text { E } & 4 & 3 & 5,000 & 7,000 \
\text { F } & 6 & 5 & 9,000 & 12,000 \
\text { G } & 10 & 8 & 5,000 & 8,000
\end{array}$$ If a deadline of 17 weeks is imposed,give the linear programming model for the crashing decision.

Accepted Answer

Let E_i = the earliest

Question 20

Activities require time to complete while events do not.

Accepted Answer

A) True 
 B)False

From this PERT/CPM network,determine the list of activities and their predecessors.

Once the earliest and latest times are calculated,how is the critical path determined?

All activities on a critical path have zero slack time.

Explain how and why all predecessor activities must be considered when finding the earliest start time.

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

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.

A critical activity is:

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

The earliest start time rule

Why should projects be monitored after the critical path is found?

The normal distribution tends to be a better approximation of the distribution of total time for shorter projects where the critical path has relatively few activities.

Which is not a significant challenge of project scheduling?

The critical path

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

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

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

To determine how to crash activity times

Activities require time to complete while events do not.

Introduction

Introduction to Probability

Probability Distributions

Decision Analysis

Utility and Game Theory

Times Series Analysis and Forecasting

Introduction to Linear Programming

Linear Programming: Sensitivity Analysis and Interpretation of Solution

Linear Programming Applications in Marketing, Finance, and Operations Management

Distribution and Network Models

Integer Linear Programming

Advanced Optimization Applications

Inventory Models

Waiting Line Models

Simulation

Markov Processes

Filters

Exam 13: Project Scheduling: Pertcpm

From this PERT/CPM network,determine the list of activities and their predecessors.

Once the earliest and latest times are calculated,how is the critical path determined?

All activities on a critical path have zero slack time.

Explain how and why all predecessor activities must be considered when finding the earliest start time.

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

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.

A critical activity is:

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

The earliest start time rule

Why should projects be monitored after the critical path is found?

The normal distribution tends to be a better approximation of the distribution of total time for shorter projects where the critical path has relatively few activities.

Which is not a significant challenge of project scheduling?

The critical path

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

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

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

To determine how to crash activity times

Activities require time to complete while events do not.

Introduction

Introduction to Probability

Probability Distributions

Decision Analysis

Utility and Game Theory

Times Series Analysis and Forecasting

Introduction to Linear Programming

Linear Programming: Sensitivity Analysis and Interpretation of Solution

Linear Programming Applications in Marketing, Finance, and Operations Management

Distribution and Network Models

Integer Linear Programming

Advanced Optimization Applications

Inventory Models

Waiting Line Models

Simulation

Markov Processes

Filters