© 2018 Cengage®. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part, except for use as permitted in a license distributed with a certain product or service or otherwise on a password-protected website or school-approved learning management system for classroom use.
Developing the Schedule
5
(Premium)
Teaching Strategies
The first vignette reinforces the need to interact with community members and key stakeholders when planning the schedule. Sometimes part of the solution of the project is the creation of other beneficial projects to help with buy in.
The second vignette reinforces that the first design of a project might not be the final plan. Complex projects require creative solutions to keep all the aspects on track and the project to be completed on time and within budget. Even though it had difficulties and a few failures at the start, the complex project was scheduled well.
Sometimes, when planning the schedule, calculated times are for activity completion are not accurate. This can become a problem when no one takes the time to examine the actual time it takes to complete activities.
Have students plan the amount of time that it would take to travel between two cities that are near campus. After they calculate the time to travel, have them think about how they would factor in extenuating circumstances (like a flat tire, the need to refill the fuel tank, the need to stop for food, or a traffic-blocking accident).
Have students calculate the ES, EF, LS, and LF times in class to be sure they understand what it means to calculate forward and to calculate backward.
The ES, EF, LS, LF times on the network diagram for the consumer market study are included in the chapter materials. Have the students compare the textbook diagram with the schedule table in Microsoft Project.
Have the students report on the similarities and the differences.
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Chapter Concepts
Estimating the resources required for each activity
Estimating the duration for each activity
Establishing the estimated start time and required completion time for the overall project
Calculating the earliest times at which each activity can start and finish, based on the project estimated start time
Calculating the latest times by which each activity must start and finish in order to complete the project by its required completion time
Determining the amount of positive or negative slack between the time each activity can start or finish and the time it must start or finish
Identifying the critical (longest) path of activities
Performing the steps in the project control process
Determining the effects of actual schedule performance on the project schedule
Incorporating changes into the schedule
Developing an updated project schedule
Determining approaches to controlling the project schedule
Implementing agile project management
Chapter Concepts
This chapter discusses monitoring and controlling the progress of the project, re-planning, and updating the project schedule.
Once a project actually begins, it is necessary to monitor progress to ensure that everything goes according to schedule. This involves measuring actual progress and comparing it to the schedule.
If at any time during the project, it is determined that the project is behind schedule, corrective action must be taken to get back on schedule, which becomes increasingly difficult as a project falls further behind.
Based on the material in this chapter, students will become familiar with:
Estimating the resources required for each activity
Estimating the duration for each activity
Establishing the estimated start time and required completion time for the overall project
Calculating the earliest times at which each activity can start and finish, based on the project estimated start time
Calculating the latest times by which each activity must start and finish in order to complete the project by its required completion time
Determining the amount of positive or negative slack between the time each activity can start or finish and the time it must start or finish
Identifying the critical (longest) path of activities
Performing the steps in the project control process
Determining the effects of actual schedule performance on the project schedule
Incorporating changes into the schedule
Developing an updated project schedule
Determining approaches to controlling the project schedule
Implementing agile project management
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© 2018 Cengage®. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part, except for use as permitted in a license distributed with a certain product or service or otherwise on a password-protected website or school-approved learning management system for classroom use.
Learning Outcomes
Estimate the resources required for activities
Estimate the duration for an activity
Determine the earliest start and finish times for activities
Determine the latest start and finish times for activities
Explain and determine total slack
Prepare a project schedule
Identify and explain the critical path
Discuss the project control process
Develop updated schedules based on actual progress and changes
Discuss and apply approaches to control the project schedule
Explain agile project management
Learning Outcomes
After studying this chapter, students should be able to:
Estimate the resources required for activities
Estimate the duration for an activity
Determine the earliest start and finish times for activities
Determine the latest start and finish times for activities
Explain and determine total slack
Prepare a project schedule
Identify and explain the critical path
Discuss the project control process
Develop updated schedules based on actual progress and changes
Discuss and apply approaches to control the project schedule
Explain agile project management
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© 2018 Cengage®. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part, except for use as permitted in a license distributed with a certain product or service or otherwise on a password-protected website or school-approved learning management system for classroom use.
Project Integration Management
Project Resource Management
Project Schedule Management
Project Management Knowledge Areas from PMBOK® Guide
Project Management Knowledge Areas from PMBOK® Guide
Concepts in this chapter support the following Project Management Knowledge Areas of the PMI Guide to the Project Management Body of Knowledge (PMBOK® Guide):
Project Integration Management
Project Resource Management
Project Schedule Management
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More than Wind Infrastructure Development in Kenya
Background
Up to 310 megawatts of clean power
€625 million wind farm
Feasibility studies
Transmission route determination
Clean water bore holes for livestock
Construct schools and medical dispensaries
Analysis and Solutions
Robust project planning
Viability
Sustainability
Schedule
Outcomes
Construct road
Relocate village
Construction Oversight
Private – windfarm
Government – transmission
Vignette A: More than Wind Infrastructure Development in Kenya
Expected to produce up to 310 megawatts of clean power to be added to the Kenyan grid, the €625 million wind farm’s schedule included such tasks as the feasibility of the area for the farm, determination of the transmission line route, completion of bore holes to access clean water for livestock, construction of schools and medical dispensaries, and numbers of meetings with stakeholders and subcontractors.
Robust project planning
Examined viability and sustainability to community
The schedule for the LTWP plan was not as simple as secure funding for the PPP, construct the wind farm, build the transmission line, and connect to the grid.
it was determined that a road was needed to be constructed through Marsabit, one of the most impoverished regions of Kenya, and a village would need to be relocated.
The private contractors in the PPP are providing oversight for the construction of the windfarm.
The government agency is providing oversight to the transmission line construction.
“The president of Kenya has been to the project site, and he’s made it clear how important this project is to the country. That support has filtered down through the community and has helped the project to progress.” The project has run smoothly from the start due to planning, relationships with stakeholders, and a well-designed schedule.
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Scheduling Terminal 5
Project Overview
Multiple designs were created
More than 20,000 suppliers
Made up of 16 major projects and 147 subprojects with costs from £1 million to £300 million
Each day, 8,000 workers reported and received 250 deliveries
Project Schedule
Think beyond the traditional methods
Constructed the roof structure offsite to test process and schedule
Delivered roof 3 months early and saved £5.5 million
Included systems testing for opening day
Had issues on opening day
Vignette B: Scheduling Terminal 5
T5 at London Heathrow Airport was designed and built to be the home for British Airways domestic and international flights and was projected to provide service for 30 million passengers annually. With plans for 62 aircraft stands, the complex design was positioned on a 260-hectare (2.6 million m2, 1.0 sq mile) site on the western end of Heathrow and was bordered by the northern and southern runways. Concourse A was planned as a four-story terminal building connected to a satellite building, Concourse B, by an underground people mover transit system. The plan also included the placement of a 4,000 space multi-story car parking garage, hotel facilities, and an air traffic control tower. Access to and from T5 included road links to the M25 motorway and an underground railway to the London Underground Piccadilly Line.
The project
Multiple designs were created before final plan submitted to planning commission.
The schedule for the construction was subject to 700 restrictions, including a requirement to divert two rivers for environmental standards.
The more than 20,000 suppliers for the project provided materials for the buildings, rails and tunnels, infrastructure, or systems.
The complete project was made up of 16 major projects and 147 subprojects with costs from £1 million to £300 million.
Each day, 8,000 workers reported to the site and received almost 250 deliveries per hour
Schedule
Think beyond the traditional methods for contracting and project performance.
Roof team constructed the roof structure at a location offsite first to test the process and schedule. The roof was delivered three months early and saved £5.5 million, much more than the £3.5 million to complete the prototype construction
Included systems testing to prepare the people and the processes for opening day.
Even though the Terminal 5 construction project seemingly had been delivered on time and on budget, not every system was ready for functionality upon opening. Finally, 12 days after its initial opening, Terminal 5 began its full flight schedule.
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Estimate Activity Resources
Resources include
People, materials, equipment, facilities
Influence on the duration
Availability of the resources
Types of resources
Sufficient quantities of resources for the activity durations
Potential conflicts with other projects may cause
Involve person with expertise in resource estimate
Estimates influence costs
Estimate Activity Resources
It is necessary to estimate the types and quantities of resources that will be required to perform each specific activity in a project.
Resources include people, materials, equipment, facilities, and so forth.
Having this information is essential in estimating how long it will take to perform each activity and the project as a whole.
A number of factors influence the duration of an activity:
Availability of the resources
Types of resources
Sufficient quantities of resources for the durations of the activities
Potential conflicts with other projects that may cause a delay
When estimating the types and quantities of resources required for each specific activity, it is valuable to involve a person who has expertise or experience with the activity.
Estimated activity resources will also be used later for estimating activity costs and determining the project budget.
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Estimate Activity Durations
Duration must be the total elapsed time
Time for the work to be done plus any associated waiting time
Estimate Activity Durations
Once the types and quantities of resources are estimated for each activity, estimates can be made for how long it will take to perform the activities.
The estimated duration for each activity must be the total elapsed time—the time for the work to be done plus any associated waiting time.
The figure above depicts the activity estimated duration for varnishing floors.
It is a good practice to have the person who will be responsible for performing a specific activity estimate the duration for that activity.
Builds buy-in from the person and generates commitments
Avoids bias that may be introduced by having one person estimate the durations for all of the activities
It is important to designate an experienced individual to estimate the durations for all the activities for which the organization or subcontractor is responsible in large projects.
Historical data can be used as a guide in estimating the durations of similar activities.
Estimated duration should be aggressive yet realistic.
Inflating estimated durations in anticipation of the project manager negotiating shorter durations is not a good practice.
Throughout the performance of the project, some activities will take longer than their estimated duration, others will take less time than estimated, and a very few may conform to the estimated duration exactly.
At the beginning of the project, it may not be possible to estimate the durations for all activities with a high level of confidence.
The project team can progressively elaborate the estimated durations as more information is becomes available to allow for more accurate estimated durations.
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Why is it a good practice to have the person who will be responsible for performing a specific activity estimate the duration for that activity?
Student Discussion
Why is it a good practice to have the person who will be responsible for performing a specific activity estimate the duration for that activity?
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Possible responses to Student Discussion
Builds buy-in from the person and generates commitments
Avoids bias that may be introduced by having one person estimate the durations for all of the activities
The designated individual uses experience to estimate the durations
Historical data can be used as a guide
Why is it a good practice to have the person who will be responsible for performing a specific activity estimate the duration for that activity?
As we just discussed, it is a good practice to have the person who will be responsible for performing a specific activity estimate the duration for that activity.
Builds buy-in from the person and generates commitments
Avoids bias that may be introduced by having one person estimate the durations for all of the activities
It is important to designate an experienced individual to estimate the durations for all the activities for which the organization or subcontractor is responsible, especially for large projects.
Historical data can be used as a guide in estimating the durations of similar activities on future projects.
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Explain the statement:
The estimated duration should be aggressive yet realistic.
Student Discussion
Explain the statement: The estimated duration should be aggressive yet realistic.
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Possible responses to Student Discussion
Durations should not be too short to try to win the contract
Inflated estimated durations is not good practice
Project manager may not be able to negotiate shorter durations
Some activities will take longer and others shorter durations than planned
As the project progresses, level of confidence for accuracy increases
Explain the statement:
The estimated duration should be aggressive yet realistic.
The estimated duration should be aggressive yet realistic means the following:
Inflating estimated durations in anticipation of the project manager negotiating shorter durations is not a good practice.
Throughout the performance of the project, some activities will take longer than their estimated duration, others will be done in less time than their estimated duration, and a few may conform to the estimated duration exactly.
At the beginning of the project, it may not be possible to estimate the durations for all activities with a level of confidence regarding their accuracy. Estimations may need to be refined as a project proceeds.
The project team can progressively elaborate the estimated durations as more information becomes available, to allow for more accurate estimated durations.
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Estimate Activity Durations
This figure depicts the network diagram for a consumer market study, with the estimated durations in days for each activity.
What are the realistic estimates for the activities shown?
What happens if an activity is delayed and will be its impact on the project?
What happens if an activity finishes early?
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Establish Project Start and Finish Times
Define the overall window for project completion
May not want to commit to a specific date
Project not start until customer has approved the contract
Delay in contract signing may impact project start
Set finish time as number of days from project start
Establish Project Start and Finish Times
It is necessary to select an estimated start time and a required completion time for the overall project. This is important in order to establish a basis from which to calculate a schedule using the estimated durations for the activities.
Define the overall window, or envelope, of time in which the project must be completed.
The contractor may not want to commit to completing the project by a specific date until the customer has approved the contract.
A delay in signing will likely impact the start date of the project.
The finish time should be stated as a number of days from the start of the project.
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Develop Project Schedule
Prior activities for schedule development
Estimate duration of each activity
Establish overall window of time for the project
Develop the schedule timetable
Earliest start and finish times based on estimated start date
Latest start and finish times based on required completion date
Develop Project Schedule
Once you have an estimated duration for each activity in the network must determine (based on durations and sequence) whether the project can be realistically finished by the required completion time.
In order to do this, the contractor should estimate the duration of each activity.
He or she should establish an overall window of time for the project.
Develop a project schedule that provides a timetable for each activity and shows:
The earliest times (or dates) at which each activity can start and finish, based on the project estimated start time (or date)
The latest times (or dates) by which each activity must start and finish in order to complete the project by its required completion time (or date)
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Earliest Start and Finish Times
Earliest start time (ES)
Earliest time at which a specific activity can begin
Earliest finish time (EF)
Earliest time by which a specific activity can be completed
EF = ES + Estimated Duration
Calculate forward through the network diagram
A. Earliest Start and Finish Times
Earliest start time (ES) is the earliest time at which a specific activity can begin
It is calculated on the basis of the project estimated start time and the estimated durations of preceding activities.
Earliest finish time (EF) is the earliest time by which a specific activity can be completed
It is calculated by adding the activity’s estimated duration to the activity’s earliest start time
EF = ES + Estimated Duration
Calculate forward through the network diagram from the beginning of the project to the end of the project.
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Rule 1:
The earliest start time for a specific activity must be the same as or later than the latest of all the earliest finish times of all the activities leading directly into that specific activity.
Rule 1:
The earliest start time for a specific activity must be the same as or later than the latest of all the earliest finish times of all the activities leading directly into that specific activity.
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Earliest Start and Finish Times Calculation
Why is the ES for “Dress Rehearsal” 10?
Earliest Start and Finish Time Calculation
This figures depicts the three activities that go into the production of a “Dress Rehearsal” for a play. You will note that “Practice Skit” has an EF of day 5; “Make Costumes” has an EF of day 10; and “Make Props” has an EF of day 4.
“Dress Rehearsal” cannot start until all three of these activities are finished, so the latest of the EFs for these three activities determines the ES for “Dress Rehearsal.”
The latest of the three EFs is day 10—the earliest finish time for “Make Costumes.”
Therefore, “Dress Rehearsal” cannot start any earlier than day 10. That is, its ES must be day 10 or later.
Even though “Practice Skit” and “Make Props” may finish sooner than “Make Costumes,” “Dress Rehearsal” cannot start because the network dependent relationships indicate that all three activities must be finished before “Dress Rehearsal” can start.
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“Identify Target Consumers”
Start date = 0
ES = Start date = 0
Duration = 3
EF = 0 + 3 = 3
“Identify Target Consumers”
In the following slides we will see the different activities and forward calculations that go into a consumer market study project.
The project estimated start date is 0 and the duration is three days.
Therefore, the earliest “Identify Target Consumers” can start is time 0, and the earliest it can finish is 3 days later (because its estimated duration is 3 days).
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“Develop Draft Questionnaire”
ES = EF Task 1 = 3
Duration = 10
EF = 3 + 10 = 13
“Develop Draft Questionnaire”
When “Identify Target Consumers” is finished on day 3, “Develop Draft Questionnaire” can start. It has an estimated duration of 10 days, so its ES is day 3 and its EF is day 13.
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“Pilot-Test Questionnaire”
ES = EF Task 2 = 13
Duration = 20
EF = 13 + 20 = 33
“Pilot-Test Questionnaire”
When “Develop Draft Questionnaire” is finished on day 13, “Pilot-Test Questionnaire” can start. It has an estimated duration of 20 days, so its ES is day 13 and its EF is day 33.
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“Review Comments & Finalize Questionnaire”
ES = EF Task 3 = 33
Duration = 5
EF = 33 + 5 = 38
“Review Comments & Finalize Questionnaire”
When “Pilot-Test Questionnaire” is finished on day 33, “Review Comments & Finalize Questionnaire” can start. It has an estimated duration of 5 days, so its ES is day 33 and its EF is day 38.
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“Prepare Mailing Labels,” "Print Questionnaire," "Develop Data Analysis Software," and "Develop Software Test Data"
ES = EF Task 4 = 38
Task 5
Duration = 2
EF = 38 + 2 = 40
Task 6
Duration = 10
EF = 38 + 10 = 48
Task 7
Duration = 12
EF = 38 + 12 = 50
Task 8
Duration = 2
EF = 38 + 2 = 40
“Prepare Mailing Labels,” "Print Questionnaire," "Develop Data Analysis Software," and "Develop Software Test Data"
When “Review Comments & Finalize Questionnaire” is finished on day 38, “Prepare Mailing Labels,” "Print Questionnaire," "Develop Data Analysis Software," and "Develop Software Test Data" can all start.
The ES for each activity is 38, but they each have different EFs.
“Prepare Mailing Labels,” has an estimated duration of 2 days, so its EF is day 40.
"Develop Data Analysis Software" has an estimated duration of 10 days, so its EF is day 48.
"Develop Data Analysis Software" has an estimated duration of 12 days, so its EF is day 50.
"Develop Software Test Data" has an estimated duration of 2 days, so its EF is day 40.
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“Mail Questionnaire & Get Responses”
Latest of Tasks 5 and 6 = 48
ES = EF Task 6 = 48
Duration = 65
EF = 48 + 65 = 113
“Mail Questionnaire & Get Responses”
When “Prepare Mailing Labels” and "Print Questionnaire" are finished, “Mail Questionnaire & Get Responses” can start.
The later of the two EF times for “Prepare Mailing Labels” and "Print Questionnaire" is 48, therefore this is the ES.
“Mail Questionnaire & Get Responses” has an estimated duration of 65 days, so its ES is day 48 and its EF is day 113.
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“Test Software”
Latest of Tasks 7 and 8 = 50
ES = EF Task 7 = 50
Duration = 5
EF = 50 + 5 = 55
“Test Software”
When "Develop Data Analysis Software" and "Develop Software Test Data" are finished, “Test Software” can start.
The later of the two EF times for “Develop Data Analysis Software" and "Develop Software Test Data" is 50.
"Test Software" has an estimated duration of 5 days, so its ES is day 50 and its EF is day 55.
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“Input Response Data”
Latest of Tasks 9 and 10 = 113
ES = EF Task 9 = 113
Duration = 7
EF = 113 + 7 = 120
“Input Response Data”
When “Mail Questionnaire & Get Responses” and "Test Software" are finished, “Input Response Data” can start.
The later of the two EF times for “Mail Questionnaire & Get Responses” and "Test Software" is 113.
"Input Response Data" has an estimated duration of 7 days, so its ES is day 113 and its EF is day 120.
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“Analyze Results”
ES = EF Task 11 = 120
Duration = 8
EF = 120 + 8 = 128
“Analyze Results”
When “Input Response Data” is finished on day 120, “Analyze Results” can start.
It has an estimated duration of 8 days, so its ES is day 120 and its EF is day 128.
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“Prepare Report”
ES = EF Task 12 = 128
Duration = 10
EF = 128 + 10 = 138
Project not complete in required time
“Prepare Report”
When “Analyze Results” is finished on day 128, “Prepare Report” can start.
It has an estimated duration of 10 days, so its ES is day 128 and its EF is day 138.
The required completion time for this entire project is 130 days. 138 days is 8 days beyond the required completion time, therefore the project was not completed in the required time.
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Schedule Table ES and EF
Schedule Table ES and EF
This figure depicts the ES and EF times for the consumer market study project we just analyzed, in a schedule table format.
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Latest Start and Finish Times
Latest start time (LS)
Latest time by which a specific activity must be started
Latest finish time (LF)
Latest time by which a specific activity must be completed
LS = LF – Estimated Duration
Calculate backward through the network diagram
Latest Start and Finish Times
Latest start time (LS) is the latest time by which a specific activity must be started in order for the entire project to be finished by its required completion time.
It is calculated by subtracting the activity’s estimated duration from the activity’s latest finish time.
Latest finish time (LF) is the latest time by which a specific activity must be completed in order for the entire project to be finished by its required completion time.
It is calculated on the basis of the project required completion time and the estimated durations of succeeding activities.
LS = LF– Estimated Duration
Calculate backward through the network diagram from the end of the project to the beginning of the project.
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Rule 2:
The latest finish time for a specific activity must be the same as or earlier than the earliest of all the latest start times of all the activities emerging directly from that specific activity.
Rule 2:
The latest finish time for a specific activity must be the same as or earlier than the earliest of all the latest start times of all the activities emerging directly from that specific activity.
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Latest Start and Finish Times Calculation
Why is the LF for “Print Posters & Brochures” 20?
Latest Start and Finish Times Calculation
These figures show two activities that emerge directly from an activity labeled, “Print Posters & Brochures.”
This project is required to be completed by day 30. Therefore, “Distribute Posters” must be started by day 20 because it has an estimated duration of 10 days, and “Mail Brochures” must be started by day 25 because it has an estimated duration of 5 days.
The earlier of these two LSs is day 20. Therefore, the latest that “Print Posters & Brochures” can finish is day 20, so that “Distribute Posters” can start by day 20.
Even though “Mail Brochures” does not have to start until day 25, “Print Posters & Brochures” must finish by day 20, or else the entire project will be delayed.
If “Print Posters & Brochures” does not finish until day 25, then “Distribute Brochures” will not be able to start until day 25.
Because “Distribute Brochures” has an estimated duration of 10 days, it will not finish until day 35, which is 5 days beyond the project required completion time.
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“Prepare Report”
Required completion = 130
LF = Complete date = 130
Duration = 10
LS = 130 - 10 = 120
“Prepare Report”
Now let us look at how to set up the backward calculations for the consumer market study project we just analyzed.
The required completion time for the project is 130 working days.
Therefore, the latest that “Prepare Report,” the last activity, can finish is day 130, and the latest that it can start is day 120 because its estimated duration is 10 days.
In order for “Prepare Report” to start on day 120, the latest that “Analyze Results” can finish is day 120. If the LF for “Analyze Results” is day 120, then its LS is day 112 because its estimated duration is 8 days.