INF3708 EXAM PACK 2023 Questions and Answers

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INF3708 EXAM PACK 2023 Questions and Answers



MAY / JUNE 2016 EXAM REVISION 1
Please attempt the INF3708 exercises as part of your exam revision. Note that the revision
of assignments & past exam papers are also very crucial for better performance. In fact,
proper understanding of the assignments & past exam papers almost guarantees a pass.


QUESTION 1:
The table below gives the estimated cash flow for three different projects (in rands R):
Year Project 1 Project 2 Project 3
0 - R 195 000 - R 160 000 - R 295 000
1 + R 15 000 + R 15 000 + R 30 000
2 + R 30 000 + R 15 000 + R 35 000
3 + R 55 000 + R 20 000 + R 50 000
4 + R 50 000 + R 35 000 + R 120 000
5 + R 55 000 + R 55 000 + R 110 000
6 + R 50 000 + R 90 000 + R 115 000

1. Calculate the Net Profit of each project. (3)
2. Based on your calculation of the Net Profit, identify which project you would
select to develop. Motivate your answer. (2)
3. Calculate of Return on Investment (ROI) of each of the projects given in the
table above. (3)
4. Based on your calculation of the ROI, identify which project you would
select to develop. (2)


QUESTION 2:
Consider the following project scenario and some questions related to it. The table below gives
the estimated cash flow for three different projects (in South African rands R):
Year Project 1 Project 2 Project 3
0 - R 170 000 - R 150 000 - R 280 000
1 - R 10 000 + R 5 000 + R 10 000
2 + R 20 000 + R 20 000 + R 30 000
3 + R 50 000 + R 30 000 + R 50 000
4 + R 50 000 + R 80 000 + R 120 000
5 + R 60 000 + R 90 000 + R 120 000
6 + R 60 000 - R 10 000 + R 120 000

1. Calculate the Net Profit of each project. (3)
2. Based on your calculation of the Net Profit, identify which project you would
select to develop. Motivate your answer. (2)
3. Calculate of Return on Investment (ROI) of each of the projects given in the
table above. (3)
4. Based on your calculation of the ROI, identify which project you would

, select to develop.(2)
2


QUESTION 3:
1. Consider the following list of tasks with dependencies and estimated durations reflected
in table Draw a CPM network (activity-on-arrow diagram) to illustrate the interaction
of activities. Include all the values in the nodes. Indicate the critical path on the diagram
Task Precedents Duration (weeks)
A - 4 2. Write down the critical path(s)
B - 3 using the letters of the tasks and
C A, B 5 calculate and write down the duration
D - 1 of the project. How many paths are
E C 5 there in total? Identify them all and
F D 2 write them down.
G E, F 5
H G 6


QUESTION 4:
1. Draw a complete Activity-on-arrow network diagram. Include the event number,
earliest date, latest date and slack on each node by completing both a forward and
backward pass. Clearly indicate the total duration and critical path.
Task Precedents Duration (days)
A None 8
B None 10
C None 8
D A 10
E A 16
F D, B 17
G C 18
H C 14
I F, G 9


QUESTION 5:
1. Draw a CPM network for the list of tasks in the table above to illustrate the interaction
of activities. Clearly identify the critical path and its duration.
Activity Precedents Duration (weeks)
A None 7
B A 10
C A 12
D B 3
E B 8
F B 7
G F 2
H D, E 5
I C 13
J C 6
K H 14
L E, F 5

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QUESTION 6:
1. Consider the following list of tasks with dependencies and estimated durations reflected
in table Draw a CPM network (activity-on-arrow diagram) to illustrate the interaction
of activities. Include all the values in the nodes. Indicate the critical path on the diagram
Task Precedents Duration (weeks)
A None 6
B None 2
C A 3
D B 2
E C 4
F D 1
G E, F 1
H G 6
I H 3
J H 1
K I, J 1
2. Write down the critical path(s) using the letters of the tasks and calculate and write
down the duration of the project. How many paths are there in total? Identify them all
and write them down.


QUESTION 7:
1. Consider the following activities with their precedents and durations. Draw a complete
Activity-on-arrow network diagram. Include the event number, earliest date, latest
date and slack on each node by completing both a forward and backward pass. Clearly
indicate the total duration and critical path.

Activity Precedents Duration (weeks)
A None 3
B A 4
C B 3
D B 10
E D 8
F D 4
G D 6
H C, E, F, G 8
I H 5
J H 5
K I 4
L J 2
M K, L 4

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QUESTION 8:
Consider the network diagram below indicating the most likely duration of each activity. The
table gives the optimistic and pessimistic durations as well.




OPTIMISTIC MOST PESSIMISTIC EXPECTED STANDARD
(a) LIKELY (m) (b) (te) DEVIATION (s)
A 2 6 10
B 4 5 9
C 7 8 9
D 2 4 12
E 4 6 8
F 3 4 11
G 4 8 9
H 2 2 5



Suppose we must complete the project within 20 weeks and suppose activity D must
be completed by week 12 as the staff member is scheduled on another project after
week 12. Use the table and calculate the following:

1. Calculate the Expected (te) values and Standard Deviation (s) for all the
activities as well as for all the events and indicate all the (te) and (s) values
on the diagram. (10)
2. Draw the PERT network to present this information. (4)
3. Calculate the Z values of event 4 as well as the last event. (4)
4. According to Figure 7.8 (p.181) in your textbook or Figure 2 (question 9 below),
what is the probability of not meeting the final target date for the total project? (2)