In the following arrow diagram example, work E can be started when work
C and work D are both finished. In other words, work E can be processed
seven days after the work is started.
Work A
Work C
2 days
5 days
Work B
Work D
Work E
2 days
3 days
2 days
Example
In the following arrow diagram, calculation for the overall number
of days required if work C can be shortened to three days is illustrated.
Work A
Work C
2 days
5 days
Shortened to 2 days
Work B
Work D
Work E
2 days
3 days
2 days
The overall number of days required is calculated as follows (before work
C is shortened to three days).
Work A (2 days) + Work C (5 days) = 7 days
Work B (2 days) + Work D (3 days) = 5 days
Seven days are needed until both work C and work D are finished, so the
overall number of days required is: 7 days + Work E (2 days) = 9 days.
If work C is shortened to three days, at most five days are needed until
work C and work D are finished. Therefore, the overall number of days required is: 5 days + Work E (2 days) = 7 days.
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