PMGT430 Network Diagram (CPM): The Critical Path Method

DETAILS: This activity is designed to help you better understand the Critical Path Method (CPM), Network Diagrams, the Forward and the Backward Pass, the Critical Path, and Slack or Float. BEFORE you even begin this assignment, you should carefully review required reading/viewing materials and conduct your own research on the topics.

ASSUMPTIONS: For this exercise, assume that the numbers represent days and the letters represent activities. We are also going to use the zero time, which means that you start at time = 0 and when you finish an activity, the subsequent activity starts on the same day, so do not add one for early starts of successor activities. For example, suppose activity A takes 2 days and is followed by activity B, activity B takes 3 days and is followed by activity C, and activity C takes 1 day. For forward pass:

Activity A begins on day 0 and ends on day 2.

Activity B begins on day 2 and ends on day 5.

Activity C begins on day 5 and ends on day 6.


Part 1:

  • Please work through the network diagram and critical path activity by clicking on the following link: critical-path-exercises-form.pdf
  • Follow the directions within the activity to complete the following: (1) determine and list all paths in the network diagram, (2) calculate the critical path by conducting a “forward pass,” (3) determine the total slack or float by conducting a “backward pass.”
  • Use the “zero” start date for your initial start and when moving from one activity to the next (see “ASSUMPTIONS” above). When going from the EF of one activity to the ES of the next, do NOT add “1” to the date. Same for the backward pass.

Part 2:

  • Please reply to the ALL of the questions listed below in the “QUESTIONS” section.
  • Create an MS Word, MS PowerPoint, or Acrobat pdf document and attach it.
  • You MUST cite at least one resource in APA style other than your required or optional reading/viewing resources.

After completion of the exercises, save your responses as a pdf file (to your desktop or other storage location) that you will then attach in the Assignment 1.3 for submission.


  1. What does the critical path signify? Are the activities on this path more important than those on non-critical paths?
  2. Describe the Critical Path Method (CPM) including the major components of this method. Are there other ways besides the CPM to sequence your work packages and activities – please describe?
  3. What is the difference in total float and free float? Can you have negative float on the critical path? If so, what would this signify? If not, why not?
  4. Describe a “forward pass” and a “backward” pass in the context of the CPM.
  5. Describe the four types of dependencies and give an example of the most common type.