OCR MEI D1 2006 January — Question 1

Exam BoardOCR MEI
ModuleD1 (Decision Mathematics 1)
Year2006
SessionJanuary
TopicPermutations & Arrangements
TypeAssignment/allocation matching problems

1 Table 1 shows a precedence table for a project. \begin{table}[h]
ActivityImmediate predecessorsDuration (days)
A-5
B-3
CA3
DA, B4
EA, B5
\captionsetup{labelformat=empty} \caption{Table 1}
\end{table}
  1. Draw an activity-on-arc network to represent the precedences.
  2. Find the early event time and late event time for each vertex of your network, and list the critical activities.
  3. Extra resources become available which enable the durations of three activities to be reduced, each by up to two days. Which three activities should have their durations reduced so as to minimise the completion time of the project? What will be the new minimum project completion time?