Edexcel D2 — Question 2 8 marks

Exam BoardEdexcel
ModuleD2 (Decision Mathematics 2)
Marks8
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicLinear Programming
TypeGame theory LP formulation
DifficultyStandard +0.3 This is a standard textbook exercise in game theory requiring knowledge of converting a zero-sum game to an LP problem. While it involves multiple steps (handling negative entries, defining variables, stating objective and constraints), each step follows a mechanical procedure taught directly in D2. The question requires careful application of a known algorithm rather than problem-solving insight, making it slightly easier than average for A-level standard.
Spec7.08a Pay-off matrix: zero-sum games7.08e Mixed strategies: optimal strategy using equations or graphical method

The payoff matrix for player A in a two-person zero-sum game with value V is shown below.
B
IIIIII
\multirow{3}{*}{A}I6\(-4\)\(-1\)
II\(-2\)53
III51\(-3\)
Formulate this information as a linear programming problem, the solution to which will give the optimal strategy for player B.
  1. Rewrite the matrix as necessary and state the new value of the game, v, in terms of V. [2 marks]
  2. Define your decision variables. [2 marks]
  3. Write down the objective function in terms of your decision variables. [2 marks]
  4. Write down the constraints. [2 marks]

Question 2:
AnswerMarks Guidance
2F FI
FJ
FK
AnswerMarks
GGI
GJ
GK
AnswerMarks
HHI
HJ
HK
Question 2:
2 | F | FI
FJ
FK
G | GI
GJ
GK
H | HI
HJ
HK
The payoff matrix for player A in a two-person zero-sum game with value V is shown below.

\begin{tabular}{c|ccc}
& \multicolumn{3}{c}{B} \\
& I & II & III \\
\hline
\multirow{3}{*}{A} & I & 6 & $-4$ & $-1$ \\
& II & $-2$ & 5 & 3 \\
& III & 5 & 1 & $-3$ \\
\end{tabular}

Formulate this information as a linear programming problem, the solution to which will give the optimal strategy for player B.

\begin{enumerate}[label=(\alph*)]
\item Rewrite the matrix as necessary and state the new value of the game, v, in terms of V. [2 marks]

\item Define your decision variables. [2 marks]

\item Write down the objective function in terms of your decision variables. [2 marks]

\item Write down the constraints. [2 marks]
\end{enumerate}

\hfill \mbox{\textit{Edexcel D2  Q2 [8]}}