CPA

Question 1

What is the problem with doing (sum of all activity durations)/minimum completion time when calculating a lower bound for the number of workers

Answer 1

It doesn’t account for the degree of overlap of the activities (due to float)
Isn’t a guarantee that the calculated number of workers will be sufficient

Question 2

Unique activity rule (Purpose of dummies)

Answer 2

Every activity must be uniquely represented in terms of its events. This requires that there can be at most one activity between any two events

Dummies ensure each activity can be represented uniquely in terms of its events

Question 2

Early and late event definitions

Answer 2

The early event time is the earliest time of arrival at the event allowing for the completion of all preceding activities.
The late event time is the latest time that the event can be left without extending the time needed for the project

Question 3

Scheduling rules

Answer 3

Always use the first available worker
If there is a choice of activities, assign the one with the smallest late finish time (must be completed earlier)