Free PMI Project Management Professional Practice Question

The statement is false. The correct standard deviation is 2 days. In PERT analysis, the standard deviation (σ) is calculated using the formula: σ = (Pessimistic - Optimistic) / 6. In this case, (25 - 13) / 6 = 12 / 6 = 2 days. This value represents the variability or uncertainty in the activity duration estimate. Project managers use this information to assess the risk associated with activity durations and to calculate the probability of completing the project within a specific timeframe. Understanding how to correctly calculate the standard deviation is crucial for accurate risk assessment and project planning.