multiple priors
When calculating the Forward Pass of the project shown below you should have no problems until you reach a node that has several incoming activities. In the figure below there is no problem with calculating the Early Event Time of node-10 and node-15. What happens at node-20?
Intuitively, we know that an event cannot take place until all the items leading to that event have occurred, therefore, whenever there is more than one activity coming into a node, the Early Event Time at that node will be equal to the latest date contributed the each of the incoming activities. There are three possibilities in our small project. The possible Early Event Time from Activity A is 6. The possible Early Event Time from Activity D is 5. The possible Early Event Time from Activity E is 10. Since the Early Event Time at node-20 cannot occur until the latest of all the possible incoming Event Times we place a 10 in the box above node-20.
