Free Practice Questions for AACE International PSP Exam

Free float is a concept in Critical Path Method (CPM) scheduling that refers to the amount of time an activity's early start can be delayed without affecting the early start of any immediately succeeding activities.

Option A refers to total float, which considers early and late dates of an activity​.

Option C also points to total float.

Option D does not define free float.

Free float is critical for project planners as it provides flexibility in scheduling without impacting downstream activities​.

 Time-Scaled Logic Diagrams:

Represent activities with respect to a time scale (e.g., a calendar).

Show logical relationships and durations in a visually aligned manner, aiding in analysis and reporting.

 Common Misconceptions:

They are not the same as pure logic diagrams (B).

While often created using computer software, manual versions are also possible, so (A) is incorrect.

They are not specifically for calculating activity durations (C).

 PSP Study Guide References:

The guide identifies time-scaled logic diagrams as a tool for better visualization of schedules, where activities align with calendar dates​.

 Conclusion: The correct answer is D, as time-scaled logic diagrams are drawn to align activities with a calendar.

 Purpose of Multiple Calendars:

Multiple calendars account for varied work/non-work periods among resources, regions, or activities, accurately representing project execution.

 Evaluation of Other Options:

B, C, D: These may be secondary benefits but are not the primary reason.

 Verification with PSP Guidelines:The PSP Study Guide emphasizes the importance of calendars for realistic scheduling (Ref: PSP Study Guide, Chapter 2A: Calendars and Constraints).

 Impact of Overrun:

Drafting (Activity C) and manufacturing (Activity D) are critical path activities.

A 5-day overrun in drafting consumes all available time for manufacturing.

Therefore, manufacturing cannot be delayed without affecting the release of the product.

 Verification with PSP Guidelines:The PSP Study Guide specifies that critical path activities have zero float, so delays propagate directly to the project finish (Ref: PSP Study Guide, Chapter 2A: Critical Path and Float).

 Late Start Formula:

Late Start (LS) is calculated as LF−DurationLF - \text{Duration}LF−Duration.

For Activity 11001: LF−25=16Jan2024LF - 25 = 16 Jan 2024LF−25=16Jan2024.

 Cross-Verification with PSP Guidelines:This formula aligns with the PSP methodology for backward pass calculations, where late start is directly computed from late finish and duration values (Ref: PSP Study Guide, Chapter 2A: Schedule Analysis).

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.

References:

PSP Study Guide (2019), Section 2A – Schedule Development, Subsection on Backward Pass Calculations.

AACE Recommended Practices, RP 10S-90, discussing Late Start and Late Finish calculations.

Periodic reporting intervals are governed by contractual requirements to ensure consistency, transparency, and compliance.

While monthly reporting (Option A) is common, the exact frequency depends on contractual agreements​.

Requests by the project manager (Option B) or owner (Option C) are secondary to stipulated contractual obligations.

The PSP Study Guide highlights the importance of adhering to contractually specified intervals for periodic reporting to align all stakeholders​.

To determine how many activities in the "normal" schedule would be affected by the constraint of no activity exceeding a two-month duration (approximately 60 days):

Review the "Normal Schedule Days" Column:Look for activities with a duration greater than 60 days in the "Normal Schedule Days" column of the table provided in the image.

Count the Affected Activities:Count all activities where the "Normal Schedule Days" value exceeds 60.

Activities with durations greater than 60 days:

Activity ID 1000: 1072 days

Activity ID 1001: 85 days

Activity ID 2001: 92 days

Activity ID 3001: 152 days

Activity ID 4001: 152 days

Activity ID 5001: 102 days

Activity ID 6001: 140 days

Activity ID 6002: 115 days

Activity ID 6003: 152 days

Activity ID 9001: 175 days

Activity ID 9002: 180 days

Activity ID 9005: 72 days

Total Count:

There are 12 activities in the "normal" schedule exceeding the 60-day duration constraint.

Verified Answer:A. 12.

Detailed Explanation with References: The constraint specifies that no activity should exceed a two-month (60-day) duration. By examining the "Normal Schedule Days" column, any activity with a duration greater than 60 days is non-compliant and therefore affected. The PSP study guide emphasizes reviewing contract requirements to ensure schedules adhere to such administrative constraints​.

Retaining existing logic means preserving the original relationships and dependencies defined in the schedule. Even if progress is recorded out of sequence, calculations adhere to the pre-established logic unless explicitly changed.

Option B reflects adjustments for out-of-sequence progress but contradicts the original logic requirement.

Option C imposes restrictions that do not align with typical CPM calculations.

Option D is incorrect as the concept exists​​.

The PSP Study Guide discusses the importance of maintaining logic integrity in CPM scheduling​.

 Crashing is a technique to reduce project duration by allocating additional resources to critical path activities. The most critical factor when crashing a schedule often pertains to external constraints that could severely disrupt progress.

 Avoiding adverse weather conditions, such as the 2023-2024 winter/wet season, is paramount since such conditions can render activities impossible or highly inefficient.

 The PSP Study Guide emphasizes that constraints, such as environmental conditions, play a pivotal role in project planning and execution. Managing these constraints effectively through schedule adjustments like crashing is critical to project success.

 Financial incentives (bonus or penalties) and cost minimization, while important, typically take secondary priority when natural constraints risk derailing the project timeline entirely (PSP Guide, Section 1.2.4 – Project Variables and Constraints).