Edexcel AS Paper 1 2018 June — Question 6

Exam BoardEdexcel
ModuleAS Paper 1 (AS Paper 1)
Year2018
SessionJune
TopicQuadratic Functions

6. \begin{figure}[h]
\includegraphics[alt={},max width=\textwidth]{f7935caa-6626-4ba8-87ef-e9bb59e1ac3e-12_599_1084_292_486} \captionsetup{labelformat=empty} \caption{Figure 1}
\end{figure} A company makes a particular type of children's toy.
The annual profit made by the company is modelled by the equation $$P = 100 - 6.25 ( x - 9 ) ^ { 2 }$$ where \(P\) is the profit measured in thousands of pounds and \(x\) is the selling price of the toy in pounds. A sketch of \(P\) against \(x\) is shown in Figure 1.
Using the model,
  1. explain why \(\pounds 15\) is not a sensible selling price for the toy. Given that the company made an annual profit of more than \(\pounds 80000\)
  2. find, according to the model, the least possible selling price for the toy. The company wishes to maximise its annual profit.
    State, according to the model,
    1. the maximum possible annual profit,
    2. the selling price of the toy that maximises the annual profit.