EN
Probabilistic critical path method PERT assumes beta distribution as probability distribution of task duration. PERT assumes that experts estimate parameters of task duration ("most likely time", "optimistic time", and "pessimistic time" for each activity) according to beta distribution nature. It's not always true. In the paper we assume that the durations of tasks are fuzzy sets. On the base of expert data we construct membership function of task duration. These fuzzy sets are used for project scheduling and for buffer size calculation. The illustrative example is presented