| Exam Board | OCR MEI |
|---|---|
| Module | S1 (Statistics 1) |
| Year | 2011 |
| Session | January |
| Marks | 3 |
| Paper | Download PDF ↗ |
| Mark scheme | Download PDF ↗ |
| Topic | Measures of Location and Spread |
| Type | Skewness identification and interpretation |
| Difficulty | Easy -1.8 This is a straightforward S1 question requiring only basic data reading skills: counting to find the mode (960g appears 3 times) and median (13th value), then observing positive skew from the stem-and-leaf diagram. No calculations or problem-solving required, just direct application of definitions. |
| Spec | 2.02f Measures of average and spread |
The stem and leaf diagram shows the weights, rounded to the nearest 10 grams, of 25 female iguanas.
\begin{align}
8 &| 3 \quad 9 \\
9 &| 3 \quad 5 \quad 6 \quad 6 \quad 6 \quad 8 \quad 9 \quad 9 \\
10 &| 0 \quad 2 \quad 2 \quad 3 \quad 4 \quad 6 \quad 9 \\
11 &| 2 \quad 4 \quad 7 \quad 8 \\
12 &| 3 \quad 4 \quad 5 \\
13 &| 2
\end{align}
Key: $11|2$ represents 1120 grams
\begin{enumerate}[label=(\roman*)]
\item Find the mode and the median of the data. [2]
\item Identify the type of skewness of the distribution. [1]
\end{enumerate}
\hfill \mbox{\textit{OCR MEI S1 2011 Q1 [3]}}