Edexcel D1 2017 June — Question 3

Exam BoardEdexcel
ModuleD1 (Decision Mathematics 1)
Year2017
SessionJune
TopicCombinations & Selection

3. \begin{figure}[h]
\includegraphics[alt={},max width=\textwidth]{39bbf9e2-efa7-4f3e-a22d-227f83184abd-04_604_506_239_406} \captionsetup{labelformat=empty} \caption{Figure 1}
\end{figure} \begin{figure}[h]
\includegraphics[alt={},max width=\textwidth]{39bbf9e2-efa7-4f3e-a22d-227f83184abd-04_608_511_242_1146} \captionsetup{labelformat=empty} \caption{Figure 2}
\end{figure} Figure 1 shows the possible allocations of six workers, Andrea (A), Baasim (B), Charlie (C), Deirdre (D), Ean (E) and Fen-Fang (F), to six tasks, 1, 2, 3, 4, 5 and 6.
  1. Write down the technical name given to the type of graph shown in Figure 1.
    (1) Figure 2 shows an initial matching.
  2. Starting from the initial matching, use the maximum matching algorithm to find a complete matching. You must list the alternating path you used and state your complete matching.
  3. State a different complete matching from the one found in (b).
  4. By considering the workers who must be allocated to particular tasks, explain why there are exactly two different complete matchings.