Which statistical probability distribution models project completion times in PERT networks_________________?
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Answer: E. Gaussian
Explanation
The overall project completion time distribution in PERT networks is modeled by the Gaussian distribution. The Central Limit Theorem ensures that the sum of multiple independent random activity durations approaches a normal curve. Using the Gaussian probability distribution allows project managers to calculate confidence intervals for project finish dates. Program Evaluation and Review Technique networks use probabilistic time estimates to handle uncertainty in task durations. Individual activity times are typically modeled using beta distributions before calculating critical path statistics. The Gaussian distribution is symmetrical and defined mathematically by its mean value and standard deviation.
Project planners use normal distribution curves to determine the statistical probability of meeting strict contract deadlines. Risk management in large engineering projects relies on Gaussian approximations to forecast schedule contingencies. Understanding project duration variance helps organizations allocate buffers against unexpected construction delays. Option B represents the binomial distribution, which models discrete success-failure trials rather than continuous durations. Option C denotes the beta distribution, which is used for individual activities rather than total project completion times. Option D represents the exponential distribution, which models time between independent Poisson process events.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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