AQA D2 2016 June — Question 6

Exam BoardAQA
ModuleD2 (Decision Mathematics 2)
Year2016
SessionJune
TopicNetwork Flows

6 The network shows a system of pipes with lower and upper capacities for each pipe in litres per second.
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    1. Find the value of the cut \(X\).
    2. Hence state what can be deduced about the maximum flow from \(A\) to \(H\).
  1. Figure 3 shows a partially completed diagram for a feasible flow of 28 litres per second from \(A\) to \(H\). Indicate, on Figure 3, the flows along the edges \(B D , B E\) and \(C D\).
    1. Using your feasible flow from part (b) as an initial flow, indicate potential increases and decreases of the flow along each edge on Figure 4.
    2. Use flow augmentation on Figure 4 to find the maximum flow from \(A\) to \(H\). You should indicate any flow augmenting paths in the table and modify the potential increases and decreases of the flow on the network.
    3. State the maximum flow and indicate a maximum flow on Figure 5. \section*{Answer space for question 6} \begin{figure}[h]
      \captionsetup{labelformat=empty} \caption{Figure 3} \includegraphics[alt={},max width=\textwidth]{34de3f03-a275-44fb-88b2-b88038bcec97-23_682_689_312_397}
      \end{figure} \begin{figure}[h]
      \captionsetup{labelformat=empty} \caption{Figure 4} \includegraphics[alt={},max width=\textwidth]{34de3f03-a275-44fb-88b2-b88038bcec97-23_935_1477_1037_365}
      \end{figure} Figure 5
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