Edexcel D1 2017 January — Question 5

Exam BoardEdexcel
ModuleD1 (Decision Mathematics 1)
Year2017
SessionJanuary
TopicSign Change & Interval Methods
TypeFloyd's Algorithm Application

5. \begin{figure}[h]
\includegraphics[alt={},max width=\textwidth]{8c9bce2c-4156-4bf6-8d02-9e01d6f11948-06_897_1499_239_283} \captionsetup{labelformat=empty} \caption{Figure 3}
\end{figure} [The total weight of the network is 106.7]
Figure 3 models a network of cycle tracks that have to be inspected. The number on each arc represents the length, in km , of the corresponding track. Angela needs to travel along each cycle track at least once and wishes to minimise the length of her inspection route. She must start and finish at A.
  1. Use an appropriate algorithm to find the tracks that will need to be traversed twice. You should make your method and working clear.
  2. Find a route of minimum length, starting and finishing at A . State the length of your route. A new cycle track, AC, is under construction. It will be 15 km long. Angela will have to include this new track in her inspection route.
  3. State the effect this new track will have on the total length of her route. Justify your answer.