* - By Arup Basu*

This Tutorial is to understand Critical Path method of finding the longest path in a Project and understanding Float,Lead and lag. It is divided into following parts . This is a most important concept used by a PMP or Project management professional and is also used by all Professionals for a Project. Please go through the following parts to understand it better.

**Part 3 : Critical Path Example - Continued from **Part 2 **Earliest Start Time, Earliest Finish Time, Late most Start Time , Late most Finish Time **

Every node has one left upper box , one right upper box , one bottom left box , one bottom right box.

The boxes are for representing the following:

- Left upper box :
**Earliest Start Time** - Right upper box :
**Earliest Finish Time** - Bottom left box :
**Late most Start Time** - Bottom right box :
**Late most Finish Time**

**Earliest Start Time **/ **Earliest Finish Time**

****To **find the Earliest times** , let us take the case of A and B .

A starts at the beginning , so the earliest that A can start is 0 days . And , A’s duration is 1 day . So earliest that A can finish is 1 day .

As A will finish on day 1 , so B cannot start before Day 2 . So Earliest Start Time for B is 2 and as B’s duration is 5 , so Earliest Finish Time of B is 6^{th} day.

We now add the Earliest Start Time and Earliest Finish Time of all nodes of the Critical path and it looks as below.

**Late most Start Time**/**Late most Finish Time**

To find the Late most Start Time and Late most Finish Time’s , lets observe the last two nodes , K and J

The Late most Finish Time of activity K is 164^{th} day . The activity K takes 2 days to complete. In order for K to end on 164^{th} day , as it takes two days to complete , it must start on 163^{rd} day . So Late most Start Time for K is 163.

Now , if K has to start on 163^{rd} day , so activity J must end on 162^{nd} day . So J’s Late most Finish Time is 162^{nd} day. Also, J takes 40 days to complete . So it must start on 123^{rd} day , which is its Late most Start Time for J.

We have to remember that both J and K are on critical path , so no delay is acceptable on these two activities.

We now put all the Earliest Start Time, Earliest Finish Time, Late most Start Time , Late most Finish Time for all activities .

Go To Part4 of this Tutorial

* - By Arup Basu*

**PMP**

- What is Critical path
- Critical Path example
- Earliest Start , Earliest Finish, Late most start, Late most Finish Time
- Float, Lead, lag

- Cause and Effect diagram
- State Transition Diagram
- Decision Tables
- Equivalence Partition
- Pairwise & Orthogonal Array Testing Tutorial
- Boundary Value

**QTP-UFT-Tutorial**

QTP-Keyword-View

Spy Tool

QTP-UFT-Object-Repository

QTP / UFT Automation Framework

Part 1

Part 2

Part 3

Part4

Part 5

Part 6

Part 7

- Using CppUnit for C++ Unit Testing
**Metrics**

Requirement churn metrics

Estimation Churn metrics

Defects per KLOC

Cyclomatic Complexity of Code metrics

CCCC tool for calculating Cyclomatic ComplexityDefect removal efficiency (DRE) metrics

Fault Density metrics

Defect Density Metrics

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