Ans: A
From the box-and-whisker diagram, the upper quartile and the lower quartile are $45$ and $25$ respectively. Therefore, the inter-quartile range
From the box-and-whisker diagram, the upper quartile and the lower quartile are $45$ and $25$ respectively. Therefore, the inter-quartile range
$\begin{array}{cl}
= & 45 – 25 \\
= & 20
\end{array}$
