Edexcel D1 2023 June — Question 8 10 marks

Exam BoardEdexcel
ModuleD1 (Decision Mathematics 1)
Year2023
SessionJune
Marks10
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicLinear Programming
TypeThree-variable constraint reduction
DifficultyChallenging +1.2 This question requires translating word problems into mathematical constraints and eliminating a variable, which is standard D1 linear programming. However, the three-variable setup with percentage/ratio constraints and the need to express everything in terms of two variables only adds moderate complexity beyond routine two-variable problems. Part (b) is straightforward substitution once constraints are established.
Spec7.06a LP formulation: variables, constraints, objective function7.06b Slack variables: converting inequalities to equations

8. A headteacher is deciding how to allocate prizes to the students who are leaving at the end of the school year. There are three categories of prize: academic, sport, and leadership.
  • Each academic prize costs \(\pounds 14\), each sport prize costs \(\pounds 8\), and each leadership prize costs \(\pounds 12\). The total amount available to spend on all prizes is \(\pounds 976\)
  • For every 5 academic prizes there must be at least 2 leadership prizes
  • At least half the prizes must be academic
  • \(20 \%\) of the prizes must be for sport
The headteacher wishes to maximise the total number of prizes.
Let \(x , y\) and \(z\) represent the number of academic, sport and leadership prizes respectively.
  1. Formulate this as a linear programming problem in \(x\) and \(y\) only, stating the objective and listing the constraints as simplified inequalities with integer coefficients. Given that the headteacher awards 16 sport prizes,
  2. calculate the corresponding number of leadership prizes that the headteacher awards. You must show your working.

8. A headteacher is deciding how to allocate prizes to the students who are leaving at the end of the school year.

There are three categories of prize: academic, sport, and leadership.

\begin{itemize}
  \item Each academic prize costs $\pounds 14$, each sport prize costs $\pounds 8$, and each leadership prize costs $\pounds 12$. The total amount available to spend on all prizes is $\pounds 976$
  \item For every 5 academic prizes there must be at least 2 leadership prizes
  \item At least half the prizes must be academic
  \item $20 \%$ of the prizes must be for sport
\end{itemize}

The headteacher wishes to maximise the total number of prizes.\\
Let $x , y$ and $z$ represent the number of academic, sport and leadership prizes respectively.
\begin{enumerate}[label=(\alph*)]
\item Formulate this as a linear programming problem in $x$ and $y$ only, stating the objective and listing the constraints as simplified inequalities with integer coefficients.

Given that the headteacher awards 16 sport prizes,
\item calculate the corresponding number of leadership prizes that the headteacher awards. You must show your working.
\end{enumerate}

\hfill \mbox{\textit{Edexcel D1 2023 Q8 [10]}}