Question

02:03:17 Question No: 03 If the indirect costs for each duration are $280 for 27 weeks, $240 1or 26 weeks, 5190 tox 25 weeks, 5140 1x 24 weeks 30 ta 7 wees optimum cost-time schedule? The client offers you $10 for every week you shorten the project tom your original network. Wordt you the Crash Time Activity Crush Cost ID (Slopes A 80 B 30 с 40 D 100 F 30 5 11 15 2 50 100 Total Dromid-1300 Time Wed D B Chat Box (ABIN BABU ve 23 Response at

Answer 1

Step 1: Identify the alternative paths and Critical path. Critical path is the path of longest duration in the network A-D-F 27 Critical path B-F C-E-F 14 26 Step 2: Project Crashing using least cost method 1. Identify and list the various alternative paths through the network and their respective duration. 2. Determine Max crash time (=Normal time - Crash time) and Crash cost per unit time = (Crash cost - Normal cost)/Max Crash Time for each activity. Also determine whether the crash cost rate remains constant as the activity is crashed, or it changes. Determine the variable crash costs by time, if they are variable. 3. Determine the critical path, i.e. the path of longest duration. Only activities along the critical path need to be crashed. 4. Identify the eligible activity on the critical path having the least crash cost per unit time, and reduce by 1 time unit at a time. See if the critical path changes as the activities along the critical path are crashed. 5. If there are multiple critical paths at any stage during the crashing. Then determine whether there is any of the activites common to the critical paths. Then calculate whether the crash cost of common activity is less than the combined crash costs of the least cost crash cost activities along the critical paths. 6. Continue crashing as long as the total benefit of crashing is more than the cost of crashing, if the objective is to minimize cost. Or continue crashing, if all the activities of the critical path are fully crashed, if the objective is to minimize project duration, irrespective of cost. Optimum time-cost schedule is as follows: 0 1 2 F 1 27 26 25 30 80 D Activity Crash Path 1 Path 2 Path 3 Project Activity Cumulative Total Indirect Client Iteration TOTAL Crashe Time A-D-F B-F C-E-F Duration Crash Cost Crash Cost Direct Cost incentive COST 27 14 26 300 280 0 580 26 13 25 30 330 240 10 560 1 25 13 25 50 380 190 20 550 In the above table, Critical path(s) after each crashing are highlighted in yellow color After crashing by 2 weeks, to further shorten the project by 1 week, we need to simultaneously crash activities C and C, Total cost of crashing is 90 (40+50), which is more than the combined benefit of reduced indirect cost and client incentive. Therefore, optimmum time-cost schedule is achieved. Optimum Time-Cost Schedule Total Project Cost 550 Project Duration 25