AQA D1 2006 June — Question 3

Exam BoardAQA
ModuleD1 (Decision Mathematics 1)
Year2006
SessionJune
TopicMinimum Spanning Trees

3 [Figure 1, printed on the insert, is provided for use in part (b) of this question.]
The diagram shows a network of roads. The number on each edge is the length, in kilometres, of the road.
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    1. Use Prim's algorithm, starting from \(A\), to find a minimum spanning tree for the network.
    2. State the length of your minimum spanning tree.
    1. Use Dijkstra's algorithm on Figure 1 to find the shortest distance from \(A\) to \(J\).
    2. A new road, of length \(x \mathrm {~km}\), is built connecting \(I\) to \(J\). The minimum distance from \(A\) to \(J\) is reduced by using this new road. Find, and solve, an inequality for \(x\).