Edexcel International A Level Business PDF - 4 Critical Path Analysis

Edexcel International A Level Business 333 Decision-making techniques 4 CRITICAL PATH ANALYSIS Revisionstation From the specification a) Nature and purpose of critical path analysis. b) Complete and interpret simple networks to identify the critical path. c) Calculate: earliest st...

Edexcel International A Level Business 333 Decision-making techniques 4 CRITICAL PATH ANALYSIS Revisionstation From the specification a) Nature and purpose of critical path analysis. b) Complete and interpret simple networks to identify the critical path. c) Calculate: earliest start time latest finish time total float. d) Limitations of using critical path analysis. Starter What tasks do you have to complete in the morning which are critical? Get dressed Get on a bus ________________ ________________ ________________ ________________ Definition: Critical Path Analysis (CPA) CPA is a management tool CPA Diagram which helps a business to looks like this identify how long a project will take and calculate the minimum time taken to finish the project. The diagrams are called You do NOT network diagrams, as they have to draw a show a network of tasks in CPA diagram in your exam a project Nature and purpose of CPA Benefits to a business of using CPA Complete and interpret simple networks to identify the critical path How a CPA diagram works – step 1 A CPA network diagram starts with a list of tasks It will show how long each task will take (duration) It will also show what order they should be carried out (preceding activities) e.g. You can’t ice a cake until its baked What tasks come before tiling the floor? How long will it take to decorate the shop? How a CPA diagram works – step 2 The start of the diagram is the start of the project (day zero) and is shown by a circular node. The 1 in the left side of the circle indicates the node number NOT the day How a CPA diagram works – step 3 The first node shows three things: Earliest day that the task can start 0 EST Node number 1 0 Latest finish time that the task can end LFT How to calculate the EST EST (top right) Where two nodes meet take the longest EST How to calculate the LFT - answer LFT bottom right Node 6: 58 - 4 = 54 Where two nodes meet take the shortest LFT Identifying the critical path This shows the tasks which, if delayed, will lead to a delay in the project. The critical path on any network is where the EST and the LFT in the nodes are the same. How to calculate the Total Float If these tasks are delayed they will delay the whole project So we need to know where there is some “total float” Float = LFT – duration – EST 15 E 54 Float = 54 - 12 -15 = 27 4 6 12 54 42 How to calculate the Free Float If these tasks are delayed they will delay the following task. So we need to know where there is some free time or “free float” Float = EST of next task – duration – EST 15 E 54 of this task 4 6 Float = 54 - 12 -15 = 27 12 54 42 Limitations of CPA Limitations of Critical Path Analysis All the data in the network diagram is based on estimates and can quickly become inaccurate e.g. if the weather turns bad on a building project or suppliers fail to turn up with a delivery The drawing up on a diagram is time consuming it may be quicker to get on with the project, especially for large projects. Resources regarded as flexible at some time during the project may be inflexible in fact. Revision Video Revision video 2 Sample practice questions  Case study for question 1  Sample question 1 Level 1 Level 2 Level 3 Level 4 1-2 3-4 5-7 8-10  Answer sample question 1 Glossary Critical path analysis; this is a management tool that shows the total time that a project takes to complete Earliest start time; the first day that the task can begin, when all tasks dependent on it are finished Latest finish time; the latest the task can finish without delaying the whole project Float time; free time in the network diagram calculated by LFT of the task – task length – EST of the task