AQA S1 2011 June — Question 1 11 marks

Exam BoardAQA
ModuleS1 (Statistics 1)
Year2011
SessionJune
Marks11
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicMeasures of Location and Spread
TypeFind median and quartiles from raw data list
DifficultyEasy -1.3 This is a straightforward S1 statistics question requiring standard procedures: identifying the mode by inspection, finding median/quartiles using cumulative frequency positions (n+1)/2 etc., calculating range, and estimating mean/SD from grouped data using midpoints. All techniques are routine recall with minimal problem-solving, though the grouped data adds minor computational work.
Spec2.02f Measures of average and spread2.02g Calculate mean and standard deviation2.02i Select/critique data presentation

1 The number of matches in each of a sample of 85 boxes is summarised in the table.
Number of matchesNumber of boxes
Less than 2391
239-2431
244-2462
2473
2484
2496
25010
25113
25216
25320
2545
255-2593
More than 2591
Total85
  1. For these data:
    1. state the modal value;
    2. determine values for the median and the interquartile range.
  2. Given that, on investigation, the 2 extreme values in the above table are 227 and 271 :
    1. calculate the range;
    2. calculate estimates of the mean and the standard deviation.
  3. For the numbers of matches in the 85 boxes, suggest, with a reason, the most appropriate measure of spread.

1 The number of matches in each of a sample of 85 boxes is summarised in the table.

\begin{center}
\begin{tabular}{|l|l|}
\hline
Number of matches & Number of boxes \\
\hline
Less than 239 & 1 \\
\hline
239-243 & 1 \\
\hline
244-246 & 2 \\
\hline
247 & 3 \\
\hline
248 & 4 \\
\hline
249 & 6 \\
\hline
250 & 10 \\
\hline
251 & 13 \\
\hline
252 & 16 \\
\hline
253 & 20 \\
\hline
254 & 5 \\
\hline
255-259 & 3 \\
\hline
More than 259 & 1 \\
\hline
Total & 85 \\
\hline
\end{tabular}
\end{center}
\begin{enumerate}[label=(\alph*)]
\item For these data:
\begin{enumerate}[label=(\roman*)]
\item state the modal value;
\item determine values for the median and the interquartile range.
\end{enumerate}\item Given that, on investigation, the 2 extreme values in the above table are 227 and 271 :
\begin{enumerate}[label=(\roman*)]
\item calculate the range;
\item calculate estimates of the mean and the standard deviation.
\end{enumerate}\item For the numbers of matches in the 85 boxes, suggest, with a reason, the most appropriate measure of spread.
\end{enumerate}

\hfill \mbox{\textit{AQA S1 2011 Q1 [11]}}