The marks of some students in a French examination were summarised in a grouped frequency distribution and a cumulative frequency diagram was drawn, as shown below.

\includegraphics{figure_1}

\begin{enumerate}[label=(\roman*)]
\item Estimate how many students took the examination. [1]
\item How can you tell that no student scored more than 55 marks? [1]
\item Find the greatest possible range of the marks. [1]
\item The minimum mark for Grade C was 27. The number of students who gained exactly Grade C was the same as the number of students who gained a grade lower than C. Estimate the maximum mark for Grade C. [3]
\item In a German examination the marks of the same students had an interquartile range of 16 marks. What does this result indicate about the performance of the students in the German examination as compared with the French examination? [3]
\end{enumerate}

\hfill \mbox{\textit{OCR S1 2010 Q1 [9]}}