Edexcel FD1 2024 June — Question 3

Exam BoardEdexcel
ModuleFD1 (Further Decision 1)
Year2024
SessionJune
TopicRoute Inspection

3. \begin{figure}[h]
\includegraphics[alt={},max width=\textwidth]{7f7546eb-0c1a-40da-bdf0-31e0574a9867-06_764_1136_258_466} \captionsetup{labelformat=empty} \caption{Figure 1}
\end{figure} [The total weight of the network is 413] Figure 1 represents a network of cycle tracks between ten towns, A, B, C, D, E, F, G, H, J and K. The number on each arc represents the length, in kilometres, of the corresponding track.
  1. Use Dijkstra's algorithm to find the shortest path from A to J. Abi needs to travel along every track shown in Figure 1 to check that they are all in good repair. She needs to start her inspection route at town G and finish her route at either town J or town K. Abi wishes to minimise the total distance required to traverse every track.
  2. By considering all relevant pairings of vertices, determine whether Abi should finish her inspection route at town J or town K. You must
    • state which tracks she will repeat in her route
    • state the total length of her route
    The direct track between town B and town C and the direct track between town H and town K are now closed to all users. A second person, Tarig, is asked to check all the remaining tracks starting at G and finishing at H. Tarig wishes to minimise the total length of his inspection route.
  3. Determine which route, Abi's or Tarig's, is shorter. You must make your working clear.