GATE 2022 AR — Planning – Question 46

Project Management and Professional Practice · Construction project management techniques e.g. PERT, CPM · 2 marks · Numerical answer

The diagram gives activity durations and early/late start/finish times in weeks. Find the interfering float of activity R, as an integer.

Diagram for GATE 2022 AR — Planning question 46

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Correct answer: 6 to 6

Explanation

For R, ES=12, EF=15, LS=24, LF=27, so total float isLS−ES=12 weeks. Its successor S has ES=21, giving free float 21−15=6. Interfering float equals total minus free float:12−6=6 weeks. It is the float that can delay the successor’s early start without delaying the allowed late schedule.

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