AQA D1 2011 January — Question 3

Exam BoardAQA
ModuleD1 (Decision Mathematics 1)
Year2011
SessionJanuary
TopicMinimum Spanning Trees

3 The following network shows the lengths, in miles, of roads connecting nine villages, \(A , B , \ldots , I\).
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    1. Use Prim's algorithm starting from \(E\), showing the order in which you select the edges, to find a minimum spanning tree for the network.
    2. State the length of your minimum spanning tree.
    3. Draw your minimum spanning tree.
  1. On a particular day, village \(B\) is cut off, so its connecting roads cannot be used. Find the length of a minimum spanning tree for the remaining eight villages.
    (2 marks)
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