CHOOSE ANY THREE OF QUESTIONS 1 TO 4 TO ANSWER. 1. (12 points) Seven activities
ID: 380360 • Letter: C
Question
CHOOSE ANY THREE OF QUESTIONS 1 TO 4 TO ANSWER. 1. (12 points) Seven activities have been identified as part of completing a larger project. These activities have been labeled A through G in the following table, which also displays their immediate predecessors as well as the optimistic (a), most probable (m) and pessimistic (b) expected completion times Immediate Predecessors Activity a 4 4 C. D The project network diagram is below Start Finish Calculate the expected time in weeks for each activity. Find the critical path and expected completion time, as well as the earliest start, earliest finish, latest start, and latest finish time for each activityExplanation / Answer
Following table presents Expected values of each activity :
ACTIVITY
OPTIMISTIC TIME( a)
NORMAL TIME (m)
PESSIMISTIC TIME ( b)
EXPECTED TIME , E = ( a + 4.m + b)/6
A
1
2
3
2.00
B
2
3
5
3.17
C
4
5
6
5.00
D
3
4
8
4.50
E
2
5
7
4.83
F
4
5
6
5.00
G
1
2
3
2.00
The parallel paths and their cumulative expected durations as follows :
Start – A-C-E-G – Finish = 2 + 5 + 4.83 + 2 = 13.83 weeks
Start – B-D-E-G – Finish = 3.17 + 4.5 + 4.83 + 2 = 14.5 weeks
Start -B – F – Finish = 3.17 + 5 = 8.17 weeks
Since , B-D-E-G has the longest duration, it forms the Critical path Duration of critical path is the expected completion time. Thus , Expected completion time = 14.5 weeks
CRITICAL PATH = START – B-D-E-G- Finish
EXPECTED COMPLETION TIME = 14.5 WEEKS
It is to be noted that all activities which are part of Critical path have ZERO slack. Thus B, D , E and G have ZERO slacks. Slack is defined as difference between Early Finish ( EF ) and Early Start ( ES) time or Difference between Late Finish ( LF) and Late Start ( LS ) time .
Slack for activities A, as well as C = 14.5 weeks – 13.83 weeks = 0.67 weeks
Slack for activity F = 14.5 – 8.17 = 6.33 weeks
The details in weeks of ES/LS/EF/LF for each activity as follows :
ACTIVITY
ES
LS
EF
LF
A
0
0.67
2
2.67
B
0
0
3.17
3.17
C
2.
2.67
7
7.67
D
3.17
3.17
7.67
7.67
E
7.67
7.67
12.5
12.5
F
3.17
9.5
8.17
14.5
G
12.5
12.5
14.5
14.5
ACTIVITY
OPTIMISTIC TIME( a)
NORMAL TIME (m)
PESSIMISTIC TIME ( b)
EXPECTED TIME , E = ( a + 4.m + b)/6
A
1
2
3
2.00
B
2
3
5
3.17
C
4
5
6
5.00
D
3
4
8
4.50
E
2
5
7
4.83
F
4
5
6
5.00
G
1
2
3
2.00
Related Questions
drjack9650@gmail.com
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.