| Exam Board | CAIE |
|---|---|
| Module | S1 (Statistics 1) |
| Year | 2015 |
| Session | June |
| Marks | 6 |
| Paper | Download PDF ↗ |
| Mark scheme | Download PDF ↗ |
| Topic | Data representation |
| Type | Draw box plot from cumulative frequency |
| Difficulty | Easy -1.2 This is a straightforward data representation question requiring routine reading from a cumulative frequency diagram to find quartiles, then drawing a box plot and applying a given outlier formula. All steps are mechanical with no problem-solving or conceptual insight required—easier than average A-level. |
| Spec | 2.02a Interpret single variable data: tables and diagrams2.02h Recognize outliers |
| Answer | Marks |
|---|---|
| (ii) | 0 1 2 3 4 5 6 7 8 9 10 |
| Answer | Marks |
|---|---|
| So no outliers AG | B1 |
| Answer | Marks |
|---|---|
| A1 2 | LQ = 2.6 med = 3.8– 3.85, UQ = 6.4– 6.6 |
| Answer | Marks | Guidance |
|---|---|---|
| Page 5 | Mark Scheme | Syllabus |
| Cambridge International AS/A Level – May/June 2015 | 9709 | 62 |
Question 3:
--- 3 (i)
(ii) ---
3 (i)
(ii) | 0 1 2 3 4 5 6 7 8 9 10
time in sec
1.5 × IQR = 1.5 × 3.8 = 5.7
LQ – 5.7 = –ve, UQ + 5.7 = 12.1 i.e. > 10
So no outliers AG | B1
B1
B1
B1 4
M1
A1 2 | LQ = 2.6 med = 3.8– 3.85, UQ = 6.4– 6.6
Correct quartiles and median on graph ft
linear from 2–10
End whiskers correct not through box
Label need seconds and linear 2–10 axis or
can have 5 values on boxplot no line
provided correct
Attempt to find 1.5 × IQR and add to UQ
or subt from LQ OR compare 1.5 × IQR
with gap 3.6 between UQ and max 10
Correct conclusion from correct working
need both
Page 5 | Mark Scheme | Syllabus | Paper
Cambridge International AS/A Level – May/June 2015 | 9709 | 62\includegraphics{figure_3}
In an open-plan office there are 88 computers. The times taken by these 88 computers to access a particular web page are represented in the cumulative frequency diagram.
\begin{enumerate}[label=(\roman*)]
\item On graph paper draw a box-and-whisker plot to summarise this information. [4]
\end{enumerate}
An 'outlier' is defined as any data value which is more than 1.5 times the interquartile range above the upper quartile, or more than 1.5 times the interquartile range below the lower quartile.
\begin{enumerate}[label=(\roman*), resume]
\item Show that there are no outliers. [2]
\end{enumerate}
\hfill \mbox{\textit{CAIE S1 2015 Q3 [6]}}