AQA D1 2006 June — Question 1 6 marks

Exam BoardAQA
ModuleD1 (Decision Mathematics 1)
Year2006
SessionJune
Marks6
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicMatchings and Allocation
TypeMaximum matching algorithm application
DifficultyEasy -1.2 This is a straightforward application of the matching algorithm with clear instructions. Students are given the initial matching and simply need to draw a bipartite graph and find one alternating path to improve the matching - a routine D1 procedure requiring minimal problem-solving or insight.
Spec7.02e Bipartite graphs: K_{m,n} notation7.02r Graph modelling: model and solve problems using graphs

1 Five people, \(A , B , C , D\) and \(E\), are to be matched to five tasks, 1, 2, 3, 4 and 5. The table shows which tasks each person can do.
PersonTasks
\(A\)\(1,3,5\)
\(B\)2,4
\(C\)2
\(D\)4,5
\(E\)3,5
  1. Show this information on a bipartite graph.
  2. Initially \(A\) is matched to task 3, \(B\) to task 4, \(C\) to task 2 and \(E\) to task 5 . Use an alternating path from this initial matching to find a complete matching.

1 Five people, $A , B , C , D$ and $E$, are to be matched to five tasks, 1, 2, 3, 4 and 5. The table shows which tasks each person can do.

\begin{center}
\begin{tabular}{ | l | l | }
\hline
Person & Tasks \\
\hline
$A$ & $1,3,5$ \\
\hline
$B$ & 2,4 \\
\hline
$C$ & 2 \\
\hline
$D$ & 4,5 \\
\hline
$E$ & 3,5 \\
\hline
\end{tabular}
\end{center}
\begin{enumerate}[label=(\alph*)]
\item Show this information on a bipartite graph.
\item Initially $A$ is matched to task 3, $B$ to task 4, $C$ to task 2 and $E$ to task 5 .

Use an alternating path from this initial matching to find a complete matching.
\end{enumerate}

\hfill \mbox{\textit{AQA D1 2006 Q1 [6]}}