OCR MEI D1 2007 June — Question 4

Exam BoardOCR MEI
ModuleD1 (Decision Mathematics 1)
Year2007
SessionJune
TopicCritical Path Analysis

4 Colin is setting off for a day's sailing. The table and the activity network show the major activities that are involved, their durations and their precedences.
ARig foresail
BLower sprayhood
CStart engine
DPump out bilges
ERig mainsail
FCast off mooring ropes
GMotor out of harbour
HRaise foresail
IRaise mainsail
JStop engine and start sailing
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  1. Complete the table in your answer book showing the immediate predecessors for each activity.
  2. Find the early time and the late time for each event. Give the project duration and list the critical activities. When he sails on his own Colin can only do one thing at a time with the exception of activity G, motoring out of the harbour.
  3. Use the activity network to determine which activities Colin can perform whilst motoring out of the harbour.
  4. Find the minimum time to complete the activities when Colin sails on his own, and give a schedule for him to achieve this.
  5. Find the minimum time to complete the activities when Colin sails with one other crew member, and give a schedule for them to achieve this.