| Exam Board | CAIE |
|---|---|
| Module | S1 (Statistics 1) |
| Year | 2020 |
| Session | Specimen |
| Marks | 5 |
| Paper | Download PDF ↗ |
| Mark scheme | Download PDF ↗ |
| Topic | Data representation |
| Type | Compare distributions using stem-and-leaf |
| Difficulty | Easy -1.2 This is a straightforward stem-and-leaf interpretation question requiring students to read values and calculate median and quartiles from a given distribution, then draw box plots. It tests basic data handling skills with minimal problem-solving—routine S1 content that's easier than average A-level questions. |
| Spec | 2.02a Interpret single variable data: tables and diagrams2.02f Measures of average and spread |
| Females | Males | |||
| (4) | 5200 | 20 | 3 | (1) |
| (9) | 988764000 | 21 | 007 | (3) |
| (8) | 87533100 | 22 | 004566 | (6) |
| (6) | 642100 | 23 | 002335677 | (9) |
| (6) | 754000 | 24 | 0112556889 | (10) |
| (4) | 9500 | 25 | 3457789 | (7) |
| (2) | 50 | 26 | 046 | (3) |
| Answer | Marks | Guidance |
|---|---|---|
| Answer | Marks | Guidance |
| females: median \$22700 | B1 | |
| Lower quartile \\(21700, Upper quartile \\)24000 | B1 | Both correct |
| Answer | Marks | Guidance |
|---|---|---|
| Answer | Marks | Guidance |
| Uniform scale and labels | B1 | Must see Salary, \$000 |
| Two box plots drawn correctly (males and females) | 2 | B1B1FT |
## Question 1(a):
| Answer | Marks | Guidance |
|--------|-------|----------|
| females: median \$22700 | B1 | |
| Lower quartile \$21700, Upper quartile \$24000 | B1 | Both correct |
---
## Question 1(b):
| Answer | Marks | Guidance |
|--------|-------|----------|
| Uniform scale and labels | B1 | Must see Salary, \$000 |
| Two box plots drawn correctly (males and females) | 2 | B1B1FT | B1 for correct graph for males — CAO; B1 for correct graph for females — FT their quartiles. Horizontal line not through box |
**Total: 3 marks**
---1 The following back-to-back stem-and-leaf diagram shows the annual salaries of a group of 39 females and 39 males.
\begin{center}
\begin{tabular}{|l|l|l|l|l|}
\hline
\multicolumn{2}{|c|}{Females} & & \multicolumn{2}{|c|}{Males} \\
\hline
(4) & 5200 & 20 & 3 & (1) \\
\hline
(9) & 988764000 & 21 & 007 & (3) \\
\hline
(8) & 87533100 & 22 & 004566 & (6) \\
\hline
(6) & 642100 & 23 & 002335677 & (9) \\
\hline
(6) & 754000 & 24 & 0112556889 & (10) \\
\hline
(4) & 9500 & 25 & 3457789 & (7) \\
\hline
(2) & 50 & 26 & 046 & (3) \\
\hline
\end{tabular}
\end{center}
Key: 2 | 20 | 3 means \$20200for females and \$20300 for males.\\
(a) Find the median and the quartiles of the females' salaries.\\
You are given that the median salary of the males is $\$ 24000$, the lower quartile is $\$ 22600$ and the upper quartile is $\$ 25300$.\\
(b) Draw a pair of box-and-whisker plots in a single diagram on the grid below to represent the data.\\
\includegraphics[max width=\textwidth, alt={}, center]{adcf5ddd-5d49-45d1-b1fb-83d702c61082-02_994_1589_1736_310}
\hfill \mbox{\textit{CAIE S1 2020 Q1 [5]}}