| Exam Board | Pre-U |
|---|---|
| Module | Pre-U 9794/3 (Pre-U Mathematics Paper 3) |
| Year | 2020 |
| Session | Specimen |
| Marks | 5 |
| Topic | Measures of Location and Spread |
| Type | Identify outliers using IQR rule |
| Difficulty | Easy -1.3 This is a straightforward statistics question requiring only basic data handling skills: ordering data to find median/quartiles (standard GCSE/AS technique) and applying the 1.5×IQR outlier rule. No conceptual difficulty or problem-solving insight needed—purely mechanical application of well-rehearsed procedures. |
| Spec | 2.02f Measures of average and spread2.02h Recognize outliers |
| Car | A | B | C | D | E | F | G | H | I | J | K | L | M | N | O |
| Mpg | 57 | 40 | 34 | 33 | 11 | 17 | 30 | 27 | 31 | 20 | 35 | 24 | 26 | 23 | 32 |
The table shows fuel economy figures in miles per gallon (mpg) for some new cars.
\begin{center}
\begin{tabular}{|c|c|c|c|c|c|c|c|c|c|c|c|c|c|c|c|}
\hline
Car & A & B & C & D & E & F & G & H & I & J & K & L & M & N & O \\
\hline
Mpg & 57 & 40 & 34 & 33 & 11 & 17 & 30 & 27 & 31 & 20 & 35 & 24 & 26 & 23 & 32 \\
\hline
\end{tabular}
\end{center}
\begin{enumerate}[label=(\alph*)]
\item Find the median and quartiles for the mpg of these 15 cars. [2]
\item Use the values in part (a) to identify any cars for which the mpg is an outlier. [3]
\end{enumerate}
\hfill \mbox{\textit{Pre-U Pre-U 9794/3 2020 Q3 [5]}}