12. Critical Path Analysis

Question 1

<p>How is Earliest Start Time defined?</p>

Answer 1

<p>How soon a task in a project can begin. It is influenced by the length of time taken by tasks which must be completed before it can begin.</p>

Question 2

<p>How is Critical Path defined?</p>

Answer 2

<p>The tasks involved in a project which, if delayed, could delay the project.</p>

Question 3

<p>How is Critical Path Analysis (CPA)/ Network Analysis?</p>

Answer 3

<p>A method of calculating the minimum time required to complete a project, identifying delays which could be critical to its competition.</p>

Question 4

<p>How is Free Float defined?</p>

Answer 4

<p>The time by which a task can be delayed without affecting the following task.</p>

Question 5

<p>How is Latest Finish Time defined?</p>

Answer 5

<p>The latest time a task in a project can finish.</p>

Question 6

<p>How is Network Diagram defined?</p>

Answer 6

<p>A chart showing the order of the tasks involved in completing a project, containing information about the times taken to complete the tasks.</p>

Question 7

<p>How is Nodes defined?</p>

Answer 7

<p>Positions in a network diagram which indicate the start and finish times of a task.</p>

Question 8

<p>How is Total Float defined?</p>

Answer 8

<p>The time by which a task can be delayed without affecting the project.</p>

Question 9

<p>What is Nature and Purpose of Critical Path Analysis?</p>

Answer 9

<p>In business, the sooner a task is completed, the better. Once completed, the business can:
<br></br>- re-direct resources to new projects,
<br></br>- Satisfy the customer,
<br></br>- Receive payment sooner, which
<br></br>- Increases efficiency and profitability
<br></br>
<br></br>- Critical Path Analysis (CPA) makes use of network diagrams to calculate the minimum time needed to complete a project.
<br></br>- CPA will allow a business to identify areas where delays may occur and whether those delays may be crucial to the timely completion of a project.
<br></br>- It is commonly used in the construction, engineering, software design, aerospace and defence industries, amongst others.</p>

Question 10

<p>Why would you use Critical Path Analysis?</p>

Answer 10

<p>- Efficiency
<br></br>- Decision Making
<br></br>- Time-based Management
<br></br>- Working Capital Control</p>

Question 11

<p>Why would you use Critical Path Analysis for Efficiency?</p>

Answer 11

<p>- Allows business to identify jobs that can be completed simultaneously and those dependent on others.
<br></br>- Allows for accurate use and delivery of resources
<br></br>- Can identify where delays may occur</p>

Question 12

<p>Why would you use Critical Path Analysis for Decision Making?</p>

Answer 12

<p>- Use of models allows for more objective decision making
<br></br>- Past experience will guide development of plans to increase accuracy</p>

Question 13

<p>Why would you use Critical Path Analysis For Time Based Management?</p>

Answer 13

<p>- Identifies tasks which can be completed together and those done in order
<br></br>- Increases efficiency by allowing resources to be used elsewhere until needed</p>

Question 14

<p>Why would you use Critical Path Analysis for Working Capital Control?</p>

Answer 14

<p>9 As with a cash flow forecast, it will allow you to see which resources are required at which time, allowing for more accurate use of working capital.
<br></br>- this is especially important if a business operates a 'just-in-time' system of stock control</p>

Question 15

<p>What are Networks?</p>

Answer 15

<p>- These are the name given to the diagrams used in Critical Path Analysis
<br></br>- Some are relatively simple requiring activities to be complete in a certain sequence, other may have to have multiple tasks completed before moving onto the next one</p>

Question 16

<p>What is Network Analysis?</p>

Answer 16

<p>- Business will frequently undertake large projects, which will require a series of tasks to be completed, in a certain order, for the project to be completed on time.
<br></br>- Network allows a business to see which activities need to be completed at certain stages for the project to be completed on time, the “critical” tasks.
<br></br>- It also allows businesses to see which jobs can be delayed and the project will still be completed on time.
<br></br>- This allows a business to “path” the tasks that must be completed in order to ensure completion.</p>

Question 17

<p>What are some Features of Network Analysis?</p>

Answer 17

<p>- Arrows and lines show tasks
<br></br>- Some tasks can be completed at the same time (B&C can both be started after A)
<br></br>- Arrows and lines cannot cross
<br></br>- Each task takes a period of time
<br></br>- Task must be completed in order
<br></br>- Circles (nodes)show the start and end of each activity
<br></br>There is always a node at the start and end of the project.
<br></br>Nodes contain information about the timings of the project.</p>

Question 18

<p>How can you calculate the Earliest Start Time?</p>

Answer 18

<p>- This is the earliest time you can start at task (EST)
<br></br>- This can be calculated by going through the diagram from start to finish and working out all the possible times an activity can start and calculating the earliest one
<br></br>- This goes in the top box on the node
<br></br>- The start node is 0, and have 0 in both of its boxes (it can finish any later than 0)</p>

Question 19

<p>How can you calculate the Latest Finish Times?</p>

Answer 19

<p>- This is the latest time a project must be finish in order to complete the task on time (LFT)
<br></br>- We work back from the End node picking the largest value routes to go back on to calculate the LFT
<br></br>- This goes in the bottom box on the node
<br></br>- The end node has the same EST and LFT</p>

Question 20

<p>What is the Critical Path?</p>

Answer 20

<p>- This shows the task which, if delayed, will lead to a delay in the project.
<br></br>- To find the Critical Path it is the route where the Earliest Start Time and Latest Finish Time are the same
<br></br>- But it also needs to be the route that takes the Longest time</p>

Question 21

<p>What is Total Float?</p>

Answer 21

<p>- Once the network diagram has been completed and the CPA identified, businesses can identify the “total float” within the project. That’s how long a certain task can be delayed without the total project time being affected. It’s calculated by:
<br></br>
<br></br>LFT of activity – EST of activity – duration
<br></br>
<br></br>- The easiest way to remember this is the bottom number of the activity node minus the total number of the node before minus the weight of the time inbetween
<br></br>- Total float only applies to task not on the critical path</p>

Question 22

<p>What is Free Float?</p>

Answer 22

<p>- This is the amount of time by which a task can be delayed without affect the following task and is calculated by;
<br></br>
<br></br>EST of the next task - EST start of this task - duration
<br></br>
<br></br>- The easiest way to remember this is the top number in the activity node minus the top number in the previous node minus the weight of the line in the middle</p>

Question 23

<p>What are the Limitations of Critical Path Analysis?</p>

Answer 23

<p>Whilst CPA is a valuable tool in project planning and project appraisal, there are limitations to the technique:
<br></br>- Information used to create estimates may be incorrect.
<br></br>- Changes may occur during the project, particularly those with long completion times.
<br></br>- Businesses should factor in contingency plans to allow for this.
<br></br>- Just because a resource has been identified in this project as being needed on a certain date, doesn’t mean to say its available. It may be being used somewhere else.
<br></br>- The larger the project, the harder to manage, due to the increased volume of tasks to be completed.</p>