Building a Cordless Vacuum Cleaner
The Bestclean is a new cordless vacuum cleaner. An analysis of the task of building the Bestclean reveals the following list of relevant activities, their immediate predecessors, and their duration.
Job Description Immediate Predecessors Normal Time(Weeks)
A Product Design 6
B Market research Plan 2
C Manufacturing and engineering A 3
D Prototype A 5
E Marketing Brochure A 3
F Cost Estimate C 2
G Testing D 3
H Market survey B,E 4
I Pricing and forecast H 2
J Final report F,G,I 2
Using the mentioned case:
1. Draw a Gantt chart for the project mentioned above.
2. Calculate the number of week required to complete the project.
(a) Draw the network as an activity-on-node network
(b) Fully analyze the network
(c) State (i) the critical path activities; (ii) project duration; (iii) floats of the non-critical activities
(d) Construct an early-start Gantt chart and resource profile for the project
Please note that you need to justify your answers.
Answers
1) Using the list of activities, its duration and predecessors from the case study a Gantt chart for the proposed sequence of activities is drawn below, showing also the late start, for the activities beyond the Critical Path (assuming that all relationships among the activities and its predecessors are End-to-Start)
Figure 1 - Gantt chart for the project
2) The number of weeks to complete the project is the sum of the duration of the activities in the Critical Path, which is: A – E – H – I – J 6 + 3 + 4 + 2 + 2 = 17 weeks.
a) We can draw the AON network, as below, with the critical path activities highlighted in red. Figure 2 - Network Diagram (AON) for the project (Early and Late dates shown)
b) As no lag has been mention, the analysis for the above network is shown below, with emphasis to the activities in the Critical Path.
WBS Task Name Predecessors Duration (weeks) Start Finish Free Slack Early Start Late Start Early Finish Late Finish
A Product Design 6 1 6 0 1
Job Description Immediate Predecessors Normal Time(Weeks)
A Product Design 6
B Market research Plan 2
C Manufacturing and engineering A 3
D Prototype A 5
E Marketing Brochure A 3
F Cost Estimate C 2
G Testing D 3
H Market survey B,E 4
I Pricing and forecast H 2
J Final report F,G,I 2
Using the mentioned case:
1. Draw a Gantt chart for the project mentioned above.
2. Calculate the number of week required to complete the project.
(a) Draw the network as an activity-on-node network
(b) Fully analyze the network
(c) State (i) the critical path activities; (ii) project duration; (iii) floats of the non-critical activities
(d) Construct an early-start Gantt chart and resource profile for the project
Please note that you need to justify your answers.
Answers
1) Using the list of activities, its duration and predecessors from the case study a Gantt chart for the proposed sequence of activities is drawn below, showing also the late start, for the activities beyond the Critical Path (assuming that all relationships among the activities and its predecessors are End-to-Start)
Figure 1 - Gantt chart for the project
2) The number of weeks to complete the project is the sum of the duration of the activities in the Critical Path, which is: A – E – H – I – J 6 + 3 + 4 + 2 + 2 = 17 weeks.
a) We can draw the AON network, as below, with the critical path activities highlighted in red. Figure 2 - Network Diagram (AON) for the project (Early and Late dates shown)
b) As no lag has been mention, the analysis for the above network is shown below, with emphasis to the activities in the Critical Path.
WBS Task Name Predecessors Duration (weeks) Start Finish Free Slack Early Start Late Start Early Finish Late Finish
A Product Design 6 1 6 0 1
References: Bibliography Kerzner, H (2009) Lewis, James P (1995). Project Planning, Scheduling & Control. Chicago: Irwin Professional Publishing. PMI Standards Committee (2008). A Guide to the Project Management Body of Knowledge (PMBOK) 4th Ed. Pennsylvania: PMI Inc. Term Definitions & Formulae (extracted from PMBOK 2008) Expression Symbol Description