AACE International PSP Planning & Scheduling Professional (PSP) Exam Exam Practice Test

Scheduling Professional Study Guide and Documents References:

The Budgeted Cost of Work Scheduled (BCWS) is the planned value of all tasks scheduled during a specific period. It is a measure used in earned value management to assess schedule adherence.

Option A defines Budgeted Cost of Work Performed (BCWP).

Option B defines the total project budget (BAC).

Option C defines the expected total cost, which is Estimate at Completion (EAC).

This answer is consistent with earned value methodologies and their application in project controls​​.

The use of a winter/wet weather seasonal calendar is essential in planning and scheduling to account for climatic conditions that can impact project timelines. The PSP Study Guide emphasizes identifying project variables, such as environmental conditions, and incorporating them into the project plan to manage risks and constraints effectively. Seasonal calendars help planners predict periods of reduced productivity, increased costs, and potential delays due to adverse weather conditions (PSP Study Guide, Subchapter 1.2.4, "Project Variables").

These calendars are particularly useful for:

Forecasting potential schedule impacts during specific periods.

Enhancing the accuracy of risk management plans (PSP Study Guide, Section 1.3.13, "Risk and Recovery Plan").

Aiding in decision-making regarding resource allocation during slow periods.

 Total Float Analysis:

Total float = Late Finish (LF) - Early Finish (EF) or Late Start (LS) - Early Start (ES).

Activity C (Draft Product Manual) lies on the critical path, so its float is 0.

 Verification with PSP Guidelines:

The PSP Study Guide defines total float as the amount of time an activity can be delayed without delaying the project (Ref: PSP Study Guide, Chapter 2A: Float Analysis).

 Definitions of Delays

Excusable Delay: These are delays not caused by the contractor and may be beyond their control. They can be compensable (entitling the contractor to both time and monetary compensation) or non-compensable (entitling only time extension). Examples include acts of God or owner-caused delays.

Non-Excusable Delay: These delays are caused by the contractor, such as poor planning or lack of resources. Non-excusable delays do not qualify for any compensation or time extensions.

Compensable Delay: A type of excusable delay caused by the owner or their representatives that entitles the contractor to both time extension and additional compensation.

Non-Compensable Delay: An excusable delay that entitles only time extension but no monetary compensation (e.g., natural disasters).

 PSP Study Guide Reference: The PSP Study Guide emphasizes understanding the types of delays to analyze their impacts on schedules and costs. Non-excusable delays, which result from the contractor's actions, are clearly categorized as not providing grounds for time extensions or additional payments​.

 Analysis for Selection:

Option A: Non-excusable delays do not provide contractors with any extensions or compensation as they result from the contractor’s responsibility.

Option B: Compensable delays provide both time and compensation and do not match the question's condition.

Option C: Non-compensable delays, though they provide no monetary compensation, can allow time extensions under certain circumstances.

Option D: Excusable delays generally entitle contractors to time extensions, with or without compensation depending on the type.

 Conclusion: The correct answer is A. Non-excusable delay, as these delays provide neither time extensions nor compensation to the contractor.

Driving Activity Concept:

The driving activity in a backward pass is the one that determines the late start or finish of the dependent activity.

Activity 10001 (Valve House - Complete) is directly dependent on its successor, Activity 11001 (Spillway - Concrete).

Backward Pass Logic:

In backward pass calculations, the late start of Activity 11001 establishes the late finish of Activity 10001 due to their finish-to-start (FS) relationship.

This makes Activity 11001 the driving activity.

Verification:

According to the PSP Study Guide, driving activities are identified based on their logical ties and the critical path's constraints (Ref: PSP Study Guide, Chapter 2A: Activity Relationships and Critical Path Analysis).

Thus, the driving activity for Activity 10001 is A. Activity 11001.

Understand the Relationship Between G and H:

The time-scaled diagram shows that Activity H starts immediately after the finish of Activity G.

This is indicative of a Finish-to-Start (FS) relationship.

Cross-Verification:

Option A: Incorrect. The relationship is visible in the diagram.

Option B: Incorrect. There is no evidence of a Start-to-Start (SS) relationship.

Option D: Incorrect. Finish-to-Finish (FF) is not applicable here.

Option C: Correct. FS relationship matches the network logic.

 To eliminate Activity B from the critical path, its dependencies must change so that its delay no longer impacts the path's completion time.

 Replacing the A → B relationship with a Finish-to-Finish with Offset (FFO) and adding an FSO (Finish-to-Start with Offset) relationship from A → C allows Activity C to proceed independently of Activity B.

 References: PSP Study Guide, Section 2.2.4 – Relationships and Calculations, explains how relationship types can influence critical path determination.

 Late Finish (LF) is calculated by adjusting the Late Start (LS) of the subsequent activity (2003) by the lag value.

 The formula, LS of 2003 - 1 day, aligns with CPM principles where the predecessor's LF must occur before the successor starts.

 The date calculation, considering lags and dependencies, results in 06 Oct 2021.

 References: PSP Study Guide, Section 2.2.4 – Relationships and Calculations, Appendix A – Sample Calculations for LF and LS relationships.

 Activity Relationships:

Activity 2002 is directly succeeded by Activity 2003 in the schedule.

The late start (LS) of Activity 2003 determines the late finish (LF) of Activity 2002, adjusted by any lags or additional constraints.

 Late Finish Calculation Formula:

LF of 2002 = LS of 2003 - 1 day.

This accounts for the predecessor-successor logic and the sequence of activities.

 Date Calculation:

Late start of 2003 = 10-06-01.

Late finish of 2002 = 10-06-01 - 1 day = 10-05-01.

 Verification:

PSP guidelines emphasize that late finish values are derived by subtracting any relevant time constraints from the successor's late start (Ref: PSP Study Guide, Chapter 2A: Backward Pass Calculations)

A cost-benefit analysis for a subcontractor like SUBCO should focus on tangible and direct impacts to the project, including their labor and equipment rates, the potential for liquidated damages in the SDOT contract, and logistical concerns such as distance from the project site (PSP Study Guide, Section 1.2.4, "Project Variables"). Pending negotiations with a different entity, such as GOUGE, are unrelated to SUBCO’s contract evaluation and are therefore not a consideration.

 Scenario Review:

Delay in the parking structure foundation is an off-critical path activity.

No impact on the overall project completion date.

 Delay Analysis:

While the foundation activity is delayed, the float ensures that no downstream activities are impacted.

 Cross-Verification:

Option B: Incorrect. Assumes a 4-day impact.

Option C: Incorrect. Overestimates delays.

Option D: Incorrect. Miscalculates delays.

Activities not on the critical path are those with positive float, meaning they can be delayed without affecting the overall project completion time. The determination of such activities requires performing a forward and backward pass calculation as per CPM (Critical Path Method) analysis principles (PSP Study Guide, Section 2.2.4, "Relationships").

For example:

Identify the critical path by analyzing total float values (typically, critical path activities have zero total float).

Exclude activities that do not fall on the critical path.

A logic loop occurs when a circular dependency is introduced, creating a scenario where activities cannot progress in a linear or logical manner.

Adding a relationship between F and I would create such a loop if existing dependencies between these or related activities already establish mutual dependencies.

 Understand Free Float:

Free float is the time an activity can be delayed without delaying the start of its immediate successor.

 Review Activity F in the Diagram:

Activity F has a successor that starts later, providing room for 2 months of free float.

 Cross-Verification:

Option A: Incorrect. Overestimates the float.

Option B: Incorrect. No float is incorrect for F.

Option C: Incorrect. 1 month is insufficient.

Option D: Correct. Matches the calculated free float for Activity F.

Activity Details (9001 - "Spillway - Concrete"):

Duration: 175 days in the Normal schedule.

To calculate Late Start (LS), the Late Finish (LF) is required. LS is calculated by subtracting the activity's duration from the LF.

Formula for Late Start (LS):LS = LF.9001 - Dur.9001.

Date Calculation:

Late Finish (LF.9001) = 11-20-02 (given or derived).

Apply the formula:LS.9001 = LF.9001 - Dur.9001= 11-20-02 - 175 days.

Cross-Verification of Dates:

After subtracting 175 days, LS.9001 = 11-20-02.

Cross-Verification with Answer Options:

Option A: Incorrect. EF (Early Finish) is not needed for this calculation.

Option B: Incorrect. Uses LS and Dur incorrectly without connecting to LF.

Option C: Incorrect. Data provided is sufficient.

Option D: Correct. Matches both the formula and the date calculation.

 Definition of a Critical Path Method (CPM) Schedule:

CPM schedules are based on network diagrams that logically link activities, showing the sequence and dependencies between them.

These schedules identify the critical path, which is the longest path through the network, determining the project's shortest possible duration.

 Evaluation of Options:

Option A: Incorrect. While CPM schedules do include tasks and timelines, the defining feature is the logical interconnection of activities.

Option B: Incorrect. CPM schedules are not limited to "risky" work; they show all activities.

Option C: Incorrect. CPM schedules use network diagrams, not just graphical representations.

Option D: Correct. The network diagram is the key characteristic of CPM schedules.

 Understand Total Float:

Total float is the amount of time an activity can be delayed without affecting the project completion date.

 Review the Network Diagram and Logic:

Activity F is not on the critical path, which allows for flexibility.

Analyzing the paths and slack in the diagram confirms that Activity F has the most total float.

 Cross-Verification:

Option A: Incorrect. Activity I is on the critical path with no float.

Option B: Incorrect. Activity C is not the most flexible.

Option D: Incorrect. Activity D has limited slack.

Option C: Correct. Activity F has the maximum total float.

 Critical Path and Delays:

A delay must impact the critical path to qualify for a time extension or compensable delay, as the critical path determines the project's overall completion time.

If the critical path is not affected, the delay is considered to have "float," which means it does not affect the project's completion date and, therefore, may not be compensable.

 PSP Study Guide References:

Delays impacting the critical path are emphasized in the PSP Study Guide under schedule analysis and delay management sections. The claimant must demonstrate that the delay impacts key project milestones and overall project completion​.

 Analysis for Selection:

Option A: Correct. A delay that does not affect the critical path does not result in additional time or compensation.

Option B: Concurrent delays involve shared responsibility and may complicate claims for compensation but are not a strict requirement for delay consideration.

Option C: Monetary harm is not directly relevant to time extension entitlement.

Option D: While planned schedules are significant, the focus is on the project's critical path, not just the contractor's planned sequence.

 Conclusion: The correct answer is A because affecting the critical path is the key determinant for entitlement to a time extension or compensable delay.

 Delay Analysis:

Analyzing delays contemporaneously ensures accurate understanding of their causes and effects, helping stakeholders mitigate impacts in real time.

Waiting until after the project introduces risks of incomplete or inaccurate records.

 PSP Study Guide References:

Contemporary delay analysis is highlighted as a best practice for effective delay resolution and management​.

 Conclusion: The correct answer is B, as contemporaneous analysis is the most effective way to address project delays.

 Preventing Structural Steel Delays:

Incorporating realistic timeframes for shop drawing review and resubmittals in the baseline schedule prevents design-related delays.

 Evaluation of Other Options:

A: Adding time buffers does not address the root cause.

C: Concurrent review may create confusion and errors.

D: Switching to post-tensioned concrete is a significant design change, not a practical solution for a scheduling issue.

 Verification with PSP Guidelines:

Adequate review time aligns with PSP scheduling best practices (Ref: PSP Study Guide, Chapter 2B: Schedule Development and Baseline Creation).

 The column volume is 2,000 cubic feet (56.64 cubic meters), and each lift using a 1.75 cubic yard bucket corresponds to: Lifts required=Column volume (cubic yards)Bucket capacity (cubic yards)\text{Lifts required} = \frac{\text{Column volume (cubic yards)}}{\text{Bucket capacity (cubic yards)}} Lifts required=Bucket capacity (cubic yards)Column volume (cubic yards)​ Convert 56.64 cubic meters to cubic yards: 56.64×1.308=74.1456.64 \times 1.308 = 74.1456.64×1.308=74.14. Lifts required=74.141.75≈133 lifts.\text{Lifts required} = \frac{74.14}{1.75} \approx 133 \text{ lifts}.Lifts required=1.7574.14​≈133 lifts.

 References: PSP Study Guide, Section 1.3.7 – Resource Calculations and Allocation, which emphasizes unit conversions and resource management.

 The Late Finish (LF) of Activity 7001, when compared with dependencies in the precedence diagram, does not align with logical flow, indicating an error in its calculation.

 Validating LF involves backward pass calculations, which must respect lags and durations.

 References: PSP Study Guide, Section 2.3.4 – Schedule Change Management, and 2.4.3 – Schedule Analysis, focus on identifying and correcting logic or calculation errors in schedules.

Crashing increases direct costs as additional resources, equipment, or expedited delivery methods are employed to shorten the project duration. The PSP Study Guide (Section 2.3.5, "Acceleration") highlights that crashing involves trade-offs between time and cost, often resulting in higher demobilization costs due to the increased deployment of equipment and resources.

Best Practices for Change Management Plans:

Effective plans are developed in the planning phase, ensuring all stakeholders understand how changes will be managed.

Evaluation of Options:

Option A: Incorrect. Stakeholders are involved during development, not just after.

Option C: Incorrect. A change management plan focuses on significant changes, not minor decisions.

Option D: Incorrect. It involves all stakeholders, not just the project controls team.

Option B: Correct. Change management plans are part of project planning.

 Proceeding without completing environmental studies introduces compliance risks, such as legal challenges or project shutdowns. This is not a feasible method for reducing the overall completion time as it contradicts environmental regulations and ethical standards.

 Methods like subcontracting (A) or reallocating resources (B) are feasible, as they leverage resource management.

 References: PSP Study Guide, Section 1.2.3 – Stakeholder Considerations, and Section 1.3.13 – Risk and Recovery Planning, which emphasize compliance with regulations and avoiding unmanageable risks.

 Calculation of Maximum Lifts Per Crane Per Day:

A single crane performs 30 lifts per day.

 Number of Cranes and Days:

3 cranes working for 5 days = 3×30×53 \times 30 \times 53×30×5.

 Total Lifts:

Total lifts = 450450450.

 Verification with PSP Guidelines:

Efficient resource calculation is critical in equipment planning (Ref: PSP Study Guide, Chapter 2A: Resource Allocation and Optimization).

 Activity 2002 in the Crashed Schedule:

Activity 2002 duration in the crashed schedule is 28 days.

Start Date: 12 August 2021.

Finish Date = Start Date + Duration (excluding non-working days).

 Calculation:

12 August + 28 days = 09 September 2021 (excluding weekends or non-working days based on typical calendars).

 Verification with PSP Guidelines:

Accurate calculation of start and finish dates aligns with scheduling best practices (Ref: PSP Study Guide, Chapter 2A: Schedule Development).

 Arrow Diagramming Method (ADM):

Also known as Activity-on-Arrow (AoA).

Activities are represented as arrows, and only finish-to-start (FS) relationships are supported.

ADM has limitations in representing other relationships like start-to-start (SS), finish-to-finish (FF), or start-to-finish (SF).

 Precedence Diagramming Method (PDM):

Known as Activity-on-Node (AoN).

Activities are represented as nodes (boxes), allowing for flexibility in logic relationships, including FS, SS, FF, and SF.

 PSP Study Guide References:

The PSP Study Guide highlights that PDM has more advanced capabilities compared to ADM, particularly in defining diverse logical relationships​.

 Conclusion: The correct answer is A, as ADM is restricted to finish-to-start logic, while PDM offers more flexibility.

 Hammock Activities (2001–2004):

Activity 2001 ("River Diversion Stage 1"): Duration = 92 days.

Activity 2002: Starts immediately after 2001, duration = 38 days.

Activity 2003: Starts immediately after 2002, duration = 15 days.

Activity 2004: Starts immediately after 2003, duration = 38 days.

 Calculate the Duration:

Total duration = 92 + 38 + 15 + 38 = 183 days.

 Cross-Verification with Answer Options:

Option A: Incorrect. Underestimates.

Option C: Incorrect. Overestimates.

Option D: Incorrect. Overestimates.

Option B: Correct. Matches the calculated duration.

 Definition of a Summary Activity (Hammock):

A summary activity, also referred to as a hammock activity, spans multiple detailed tasks and is governed by the earliest start (ES) of the first task and the latest finish (LF) of the last task.

 Activities 6001 through 6003 Overview:

6001: Starts after 5001 (Drill and Grout Dam Site).

6003: Ends before 8001 (Rock Fill to elevation 50).

 Identifying Predecessor and Successor:

Predecessor: Activity 5001 (Drill and Grout Dam Site).

Successor: Activity 8001 (Rock Fill to elevation 50).

 Cross-Verification:

Logical and temporal dependencies confirm that Activity 5001 must precede the hammock, and Activity 8001 must succeed it (Ref: PSP Study Guide, Chapter 2A: Logical Sequencing and Activity Relationships

 Schedule Update Procedures:

Accurate schedule updates rely on entering actual data (start/finish dates, durations) and evaluating impacts of changes.

"Downstream" logic revisions may be needed but are less critical compared to ensuring accurate historical data and reflecting immediate changes.

 PSP Study Guide References:

Schedule updating emphasizes capturing accurate historical data and estimating remaining durations accurately​.

 Analysis of Options:

Option A and B: Key to progress tracking and forecasting.

Option D: Essential for reflecting impacts of delays and change orders.

Option C: While important, downstream logic revisions are less immediate compared to other procedures.

 Conclusion: The correct answer is C, as downstream logic revisions are less critical in achieving an accurate schedule forecast compared to other updates

A

 Critical Path Characteristics:

The critical path is the sequence of activities that determines the overall project duration.

It represents the longest duration path through the network and typically has zero float unless delays or constraints introduce negative float.

 PSP Study Guide References:

Critical path analysis is a foundational concept in schedule management, as covered extensively in the PSP guide​.

 Analysis of Options:

Option A: Correct. The critical path always has the longest duration.

Option B: Zero float is common but not universal due to constraints or delays.

Option C and D: Negative float describes specific scenarios but does not define the critical path universally.

 Conclusion: The correct answer is A, as the critical path is the longest-duration path through the network.

 Calculation of Total Lifts Required:

3 column pours = 28×3=8428 \times 3 = 8428×3=84.

Additional lifts = 150150150.

Total lifts = 84+150=23484 + 150 = 23484+150=234.

 Lifts Per Day with One Crane:

1 crane performs 30 lifts per day.

 Required Duration:

Minimum planned working duration = ⌈234÷30⌉=18\lceil 234 \div 30 \rceil = 18⌈234÷30⌉=18.

 Verification with PSP Guidelines:

Aligning workload with equipment capacity ensures practical schedule planning (Ref: PSP Study Guide, Chapter 2B: Workload Balancing).

 Project Initial Planning:

Initial planning focuses on defining project scope, tasks, durations, and logical relationships to establish a baseline schedule.

Resource Identification and Leveling is typically part of detailed scheduling and execution planning phases, not the initial planning.

 PSP Study Guide References:

Resource identification is covered under detailed schedule development, whereas initial planning emphasizes tasks, durations, and dependencies​.

 Analysis for Selection:

Option A: Not required in initial planning.

Option B: Defining durations is fundamental to planning.

Option C: Identifying tasks is essential to building the schedule.

Option D: Logical relationships ensure task dependencies are understood.

 Conclusion: The correct answer is A, as resource identification and leveling are subsequent processes in scheduling rather than initial planning.

Total float measures the flexibility in an activity’s timing within a schedule. It is defined as the amount of time an activity can be delayed without affecting the project’s overall completion date or the completion date of any of its successors.

Option A, B, and D accurately describe total float: it is calculated as the difference between early and late start/finish dates, can be positive or negative, and is associated with project completion​.

Option C describes free float, not total float, and thus is incorrect.

The Estimate to Complete (ETC) quantifies the cost required to complete all remaining work.

Option A (Budget at Completion - BAC) is the total approved budget.

Option B (Budgeted Cost of Work Performed - BCWP) measures earned value.

Option D (Estimate at Completion - EAC) includes both actual costs to date and ETC.

ETC is used to forecast project completion costs as outlined in standard project management practices​​.

Column Pour Requirements:

Each column pour requires 60 lifts per day.

Crane Capacity:

Each crane can perform 35 lifts per day.

Determine Minimum Cranes Required:

Minimum Cranes = Column Lifts ÷ Crane Capacity = 60 ÷ 35 ≈ 1.71 cranes.

Since partial cranes cannot be used, round up to 3 cranes.

Cross-Verification:

Option A (2 cranes): Incorrect. Insufficient lifts per day.

Option B (1 crane): Incorrect. Infeasible.

Option C (4 cranes): Incorrect. Exceeds requirement.

Option D (3 cranes): Correct. Satisfies lift requirements efficiently.

 Impact of Calendars on Total Float:

Differing calendars (e.g., working days, holidays, or shifts) assigned to activities can result in varying total float values within a logical chain.

Total float measures the flexibility of an activity and is calculated based on its calendar and logical dependencies.

 PSP Study Guide References:

The guide covers how calendar assignments influence float calculations and their potential to create disparities in a critical path​.

 Conclusion: The correct answer is B, as differing total float values typically indicate the use of different calendars for activities in the chain.

 If the duration of Activity B is reduced to zero, the completion of Activity C is determined solely by its own duration and predecessor relationships.

 Without knowing the explicit network logic, it is inferred that reducing Activity B to zero does not affect Activity C’s finish on Day 50, as its relationship with other activities remains intact.

 References: PSP Study Guide, Section 2.2.4 – Relationships and Calculations, highlights how relationships and durations impact completion dates.

 Mitigating Late Completion:

A procurement agent could monitor and expedite long-lead equipment, reducing delivery delays that often affect project timelines.

 Evaluation of Other Options:

A: Hiring a senior project manager may not address the specific issue.

B: Self-performing may not resolve procurement delays.

D: Better structural steel drawings relate to design, not equipment delays.

 Verification with PSP Guidelines:

PSP emphasizes early identification and mitigation of procurement risks (Ref: PSP Study Guide, Chapter 2B: Procurement and Supply Chain Management).

 Calculation of Productivity Loss:

Subtracting productivity during an impacted period from unimpacted productivity quantifies the reduction in efficiency or loss in productivity.

 PSP Study Guide References:

Productivity analysis includes evaluating impacted vs. unimpacted periods to assess losses​.

 Conclusion: The correct answer is C, as the difference represents productivity loss.

 Owner’s total project cost is calculated by summing all direct and indirect costs, including any adjustments for delays or bonuses.

 Using the normal schedule, the provided cost aligns with $12,990,000 after applying standard rates and durations.

 References: PSP Study Guide, Section 1.3.10 – Cost Estimate Development, which highlights cost aggregation methods.

 Situation Analysis:

A 5-day delay in product release impacts the printing window.

The printer is further delayed by 10 workdays.

 Total Delay Impact Calculation:

The combined impact of the testing and printing delays = 5 + 10 = 15 days.

This results in a cumulative delay in product release.

 Cross-Verification:

Option B: Incorrect. Ignores delays entirely.

Option C: Incorrect. Assumes only one source of delay.

Option D: Incorrect. Underestimates delay impact.

Option A: Correct. Matches the calculated total delay.

 Assumptions in Planning:

Assumptions are placeholders until verified facts are available. Replacing them enhances schedule reliability and accuracy.

 Evaluation of Other Options:

A: Shifting risks is not a proactive solution.

C: Sole reliance on experience without verification is risky.

D: Internal memos clarify assumptions but do not replace facts.

 Verification with PSP Guidelines:

PSP emphasizes validating assumptions during the planning phase (Ref: PSP Study Guide, Chapter 1B: Planning Fundamentals).

 Shape of Cumulative BCWS:

The Budgeted Cost of Work Scheduled (BCWS) reflects a cumulative expenditure curve over time, typically shaped like an "S".

 Explanation of the S-Curve:

Initially slow expenditure, acceleration during peak work, and tapering off near completion.

 Verification with PSP Guidelines:

The PSP Study Guide discusses BCWS as part of earned value management (Ref: PSP Study Guide, Chapter 1D: Earned Value Analysis).

Scheduling Professional Study Guide and Documents References:

Total float is the amount of time an activity can be delayed without delaying the project's overall completion date.

Option B (buoyancy) and Option D (end of that activity) are irrelevant.

Option C refers to free float, not total float.

This definition is fundamental in critical path analysis​​.

Resource-leveling is used when resource constraints such as labor, materials, or equipment availability might prevent schedule logic from being followed.

Option A references float-banking, unrelated to resource leveling.

Option C suggests never performing leveling unless required, which overlooks the need to address actual resource limitations.

Option D is incorrect as a resource-loaded schedule may still need leveling for optimization.

Resource management principles in the PSP Study Guide discuss when and why to apply resource leveling​​.

Analyze the Relationship Details:The table shows that Activity 3001 ("Excavation, Dam Site") and Activity 4001 ("Excavation, Spillway") have a Start-to-Start (SS) relationship with a lag of 15 days. A Start-to-Start relationship indicates that the successor activity (4001) can only start after a specified lag period once the predecessor activity (3001) begins.

Understand the Concept of Lag:In scheduling terminology, lag refers to a delay or waiting period between the start (or finish) of one activity and the start (or finish) of a dependent activity. Here, the 15-day lag means that Activity 4001 will commence 15 days after Activity 3001 has started.

Interpret the Relationship:The SS relationship combined with a lag indicates that the two activities (3001 and 4001) are not starting exactly at the same time but are still overlapping or concurrent. This concurrency happens after the lag period elapses.

Verify PSP Study Guide and Relevant Terminology:According to AACE International’s Recommended Practices and the PSP Certification Study Guide:

Start-to-Start relationships are widely used to model overlapping work in schedules where one activity can start before its predecessor is fully complete (PSP Study Guide, Chapter on Scheduling Relationships and Constraints).

Lags provide flexibility to model realistic conditions where tasks start partially overlapping or with delays (PSP Study Guide, Section 2.2.4 Relationships).

Cross-Check the Answer Options:

Option A (Correct): Matches the described logic – "These activities are concurrent with Activity 4001 starting 15 days after the start of Activity 3001."

Option B: Incorrect – Lag is applied to the successor activity, meaning 4001 cannot start earlier than 3001.

Option C: Incorrect – This relationship (SS with a lag) indicates concurrency, not series.

Option D: Incorrect – Though concurrent, the lag makes the start times offset by 15 days, so they do not start at the same time.

 Critical Path Characteristics:

The critical path is the longest path through the network, defining the minimum project completion time. It cannot be the shortest path.

 PSP Study Guide References:

Critical path analysis emphasizes that it is determined by network logic and represents the chain of activities controlling the project duration​.

 Analysis for Selection:

Option A, C, and D: Accurately describe the critical path.

Option B: Incorrect; the critical path is not the shortest path.

 Conclusion: The correct answer is B, as the critical path is the longest path, not the shortest.