Edexcel D1 2018 January — Question 3

Exam BoardEdexcel
ModuleD1 (Decision Mathematics 1)
Year2018
SessionJanuary
TopicShortest Path

3. \begin{figure}[h]
\includegraphics[alt={},max width=\textwidth]{e0c89aba-9d2e-469b-8635-d513df0b65a4-04_1059_1424_228_317} \captionsetup{labelformat=empty} \caption{Figure 4}
\end{figure} Figure 4 represents a network of train tracks. The number on each edge represents the length, in kilometres, of the corresponding track. Sally wishes to travel from A to J. She wishes to minimise the distance she travels.
  1. Use Dijkstra's algorithm to find the shortest path from A to J. State the path and its length.
  2. Find a route of minimal length that goes from D to H via A and state its length.
  3. Use Prim's algorithm, starting at E , to find a minimum spanning tree for the network. You must clearly state the order in which you select the edges of your tree.
  4. Find the length, in kilometres, of your minimum spanning tree.