Edexcel D1 2012 January — Question 2

Exam BoardEdexcel
ModuleD1 (Decision Mathematics 1)
Year2012
SessionJanuary
TopicRoute Inspection

2. \begin{figure}[h]
\includegraphics[alt={},max width=\textwidth]{e02c4a9a-d2ab-489f-b838-9b4d902c4457-3_650_1357_260_354} \captionsetup{labelformat=empty} \caption{Figure 2
[0pt] [The weight of the network is 129 miles]}
\end{figure} Figure 2 models a network of canals. The number on each arc gives the length, in miles, of that canal. Brett needs to travel along each canal to check that it is in good repair. He wishes to minimise the length of his route.
  1. Use the route inspection algorithm to find the length of his route. State the arcs that should be repeated. You should make your method and working clear. A canal between B and F , of length 12 miles, is to be opened and needs to be included in Brett's inspection route.
  2. Determine if the addition of this canal will increase or decrease the length of Brett's minimum route. You must make your reasoning clear.