Quick Answer: What Is The PERT Formula?

What is optimistic time in Pert?

Optimistic time is a concept used in the program evaluation and review technique (PERT).

It represents the shortest estimated time period within which a task is likely to be completed, and is used in project planning..

What is the formula for calculating pert?

PERT is an estimating technique that uses a weighted average of three numbers (see below) to come up with a final estimate. The resulting PERT estimate is calculated as (O + 4M + P)/6. This is called a “weighted average” since the most likely estimate is weighted four times as much as the other two values.

What is difference between PERT and CPM?

PERT is that technique of project management which is used to manage uncertain (i.e., time is not known) activities of any project. … CPM is that technique of project management which is used to manage only certain (i.e., time is known) activities of any project.

What is the difference between PERT and Gantt charts?

Essentially, a Gantt chart is a bar chart that lays out project tasks and timelines linearly. … A PERT chart, on the other hand, is structured as a flow chart or network diagram that displays all the project tasks in separate boxes and connects them with arrows to clearly show task dependencies.

What three estimates does the PERT calculation?

There are three estimation times involved in PERT; Optimistic Time Estimate (TOPT), Most Likely Time Estimate (TLIKELY), and Pessimistic Time Estimate (TPESS). In PERT, these three estimate times are derived for each activity.

How do you calculate a 3 point estimate?

Three-point Estimate (E) is based on the simple average and follows triangular distribution.E = (O + M + L) / 3.Step 1 − Arrive at the WBS.Step 2 − For each task, find three values − most optimistic estimate (O), a most likely estimate (M), and a pessimistic estimate (L).More items…

What is a PERT diagram used for?

A PERT chart is a visual project management tool used to map out and track the tasks and timelines.

What is PERT chart with Example?

A PERT chart uses circles or rectangles called nodes to represent project events or milestones. These nodes are linked by vectors or lines that represent various tasks. Dependent tasks are items that must be performed in a specific manner. For example, if an arrow is drawn from Task No.

How do you use PERT?

PERT stands for Program Evaluation and Review Technique….Follow these steps to put your PERT chart together:List all of the activities involved in the project.Consider dependencies.Place nodes and arrows based on the information you have gathered.Add completion time for each activity.

How do you find the probability of pert?

The probability distribution for expected time is calculated by the following equation: Expected time = (Optimistic Time + 4 x Most likely Time + Pessimistic Time) / 6. Add the Optimistic Time for a subproject to the Pessimistic time for the same subproject.

How do you do PERT analysis?

Program Evaluation and Review Technique (PERT) is a method used to examine the tasked that are in a schedule and determine a variation of the Critical Path Method (CPM). It analyzes the time required to complete each task and its associated dependencies to determine the minimum time to complete a project.

What is PERT time estimate?

PERT is a project management planning tool used to calculate the amount of time it will take to realistically finish a project. PERT stands for Program Evaluation Review Technique.

How do I create a PERT diagram?

How to develop a PERT chartStep 1: List out your project milestones and tasks. … Step 2: Identify the sequence of those tasks. … Step 3: Determine the time criteria for your tasks. … Step 4: Draw up your PERT diagram. … Step 5: Draw out your critical path. … Step 6: Update your PERT chart as needed.

What is the main advantage of pert?

A PERT chart enables you to create milestones for your project. During the time between each milestone, you can use the chart to identify any possible outcomes or obstacles that your project may face. This means you can quickly address them, or prepare for them, to help your project stay on track.