| Exam Board | OCR MEI |
|---|---|
| Module | S1 (Statistics 1) |
| Year | 2010 |
| Session | January |
| Marks | 8 |
| Paper | Download PDF ↗ |
| Mark scheme | Download PDF ↗ |
| Topic | Measures of Location and Spread |
| Type | Construct stem-and-leaf then find median and quartiles |
| Difficulty | Easy -1.3 This is a straightforward data handling question requiring only basic statistical skills: ordering data, constructing a stem-and-leaf diagram (a standard S1 technique), and calculating simple summary statistics (median and midrange). Part (iii) requires minimal interpretation. No problem-solving or conceptual depth is needed—purely routine application of taught methods. |
| Spec | 2.02a Interpret single variable data: tables and diagrams2.02f Measures of average and spread |
A camera records the speeds in miles per hour of 15 vehicles on a motorway. The speeds are given below.
$$73 \quad 67 \quad 75 \quad 64 \quad 52 \quad 63 \quad 75 \quad 81 \quad 77 \quad 72 \quad 68 \quad 74 \quad 79 \quad 72 \quad 71$$
\begin{enumerate}[label=(\roman*)]
\item Construct a sorted stem and leaf diagram to represent these data, taking stem values of 50, 60, ... . [4]
\item Write down the median and midrange of the data. [2]
\item Which of the median and midrange would you recommend to measure the central tendency of the data? Briefly explain your answer. [2]
\end{enumerate}
\hfill \mbox{\textit{OCR MEI S1 2010 Q1 [8]}}