Project Planning, Scheduling, and Controls
This domain tests planning and control of scope, schedule, cost, and risk. Expect WBS, dependency, critical-path, float, earned-value, baseline, and change-control questions with dates or cost data.
Core rules and concepts
- WBS follows the 100% rule: child elements sum to the parent scope without overlap.
- CPM: forward pass gives early dates; backward pass gives late dates; total float = LS−ES = LF−EF. Critical path has zero total float or minimum float.
- Free float is delay possible without affecting the earliest start of any successor.
- Earned value: CV=EV−AC; SV=EV−PV; CPI=EV/AC; SPI=EV/PV. EAC depends on the forecast assumption; EAC=BAC/CPI if current cost efficiency continues.
- Changes go through integrated change control: assess scope, schedule, cost, risk, and baseline before approval.
Worked example
BAC=$500k, PV=$200k, EV=$180k, AC=$190k. CV=180−190=−$10k (over budget); SV=180−200=−$20k (behind schedule); CPI=180/190=0.947; SPI=180/200=0.90. If CPI continues, EAC=500/0.947=$527.8k. Reasoning: EV compares completed work to both plan and actual cost; AC alone is not schedule performance.
Traps that cost marks
- Using AC in SV or PV in CPI.
- Calling a task critical because it is important or expensive.
- Confusing total float with free float.
- Accepting percent-complete claims without verified EV.
- Re-baselining without approved change.