Chapter 13, Problem 11CT

To determine

To find the lower and upper quartile and sketch a box-and-whisker plot for the given data.

Answer to Problem 11CT

Lower quartile $=21.5$

Upper quartile $=28$

Explanation of Solution

Given information:

  $25,20,22,28,24,28,25,19,27,29,28,21$

Order the data in ascending order,

  $19,20,21,22,24,25,25,27,28,28,28,29$

Finding lower quartile,

  $\begin{array}{l}\left(19,20,21,22,24,15\right)\\ \frac{21+22}{2}=21.5\end{array}$

Finding upper quartile,

  $\begin{array}{l}\left(25,27,28,28,28,29\right)\\ \frac{28+28}{2}=28\end{array}$

  

Thus we can find the lower quartile and upper quartile of the given set of data.