CAIE S1 2020 June — Question 3

Exam BoardCAIE
ModuleS1 (Statistics 1)
Year2020
SessionJune
TopicMeasures of Location and Spread
TypeInterpret or analyse given back-to-back stem-and-leaf

3 Two machines, \(A\) and \(B\), produce metal rods of a certain type. The lengths, in metres, of 19 rods produced by machine \(A\) and 19 rods produced by machine \(B\) are shown in the following back-to-back stem-and-leaf diagram. \begin{table}[h]
\(A\)\(B\)
21124
76302224556
8743112302689
55532243346
4310256
\captionsetup{labelformat=empty} \caption{Key: 7 | 22 | 4 means 0.227 m for machine \(A\) and 0.224 m for machine \(B\).}
\end{table}
  1. Find the median and the interquartile range for machine \(A\).
    It is given that for machine \(B\) the median is 0.232 m , the lower quartile is 0.224 m and the upper quartile is 0.243 m .
  2. Draw box-and-whisker plots for \(A\) and \(B\).
    \includegraphics[max width=\textwidth, alt={}, center]{a3b3ebd1-db9e-4552-9abe-bfdeba786d02-05_812_1205_616_511}
  3. Hence make two comparisons between the lengths of the rods produced by machine \(A\) and those produced by machine \(B\).