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What is Critical Path Analysis?

List all the tasks needed to finish the project
Find the longest path of tasks (this is called the critical path)
See how long the project will take
Know which tasks are most important and must be done on time

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Critical Path

👉 If a task on the critical path is late, the whole project will be late.

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Bobo Pizza

There is a family-run pizza restaurant in Town X called Bobo Pizza that serves amazing pizza and is very successful even though none of the family members running the restaurant have a business degree. The restaurant has been serving the best pizza in town for more than 10 years and looks a little bit outdated, so Bobo Pizza management shut it down for a month for renovation. A wonderful and smart IB BM student (you) who happened to know about the Bobo Pizza renovation project decided to see if it could have been completed in less than a month. All the renovation tasks and their duration are summarised below.

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As you can see from the table above, task D (installation of new kitchen equipment) can only start after task B is completed (removal of old kitchen equipment). At the same time, task E (repainting the walls in the dining area) can only begin after task C is completed (removing old furniture from the dining area). Lastly, task F (new dining area furniture assembly) can only commence after task E is completed (repainting the walls in the dining area). Tasks B, C, D, E, and F are allocated to one of the two rooms in the building (kitchen and the dining area), while tasks A and G are for the entire building.

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Duration of project tasks under arrows that represent the project tasks:

Question: Complete the rest of the Critical Path Diagram

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Lewinski Above Diagram (ANSWER Question 2)

Question 3: Complete the rest of the Critical Path Analysis

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Lewinski Above Diagram (ANSWER Question 3)

Question 4: Identify the Critical Path

Question 5: Calculate the Float (Slack) time of activity B

Question 6: Calculate the Float time of activity D

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Question 4: Critical Path: A, C, E, F, G

This is because if any of these activities are delayed then the entire project will be delayed.

Question 5: The Float (Slack) time of Activity B is 5 Days

Question 6: The Float (Slack) time of Activity D is 5 Days

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Advantages - Critical Path Analysis

Better planning

Helps you organize the project step by step.�

Use time and people better

Shows which tasks are urgent and which can wait.�

Find problems early

You can see where delays might happen.�

Helps with decisions

You can choose what to do if something goes wrong.�

Easy to show to others

Diagrams help teams understand the project clearly.

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Disadvantages - Critical Path Analysis

Takes time to make

Especially if the project is big.�

Only guesses time

If you guess wrong, the plan won’t work well.�

Doesn’t solve all problems

It only shows time, not cost or team issues.�

Needs updates

You must change it if the project changes.�

No information about cost or people

Only shows time, not how much money or how many workers are needed.

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Hard Example

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Free Float Time Formula

Free Float = EST of next Activity - Earliest finish of this activity*

Earliest finish = Earliest start + time to complete

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Complete the rest of the Critical Path Diagram
Identify the Critical Path
Calculate the Total Float time for L
Calculate the Total Float time for K
Calculate the Free Float time for C

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ANSWERS

Complete the rest of the Critical Path Diagram

X = 2+4 = 6

Y = 22 - 5 = 17

Identify the Critical Path

F, H, J, K

Calculate the Total Float time for L

Total Float = LFT - Duration - EST

22 - 5 - 12 = 5

Calculate the Total Float time for K