Question

For the following sample what is the value of the lower adjacent(lower wisker)?

10, 23, 25, 26, 27, 28, 29, 30, 42, 45

Answer 1

We know that the length of the whiskers of a boxplot is 1.5 times the interquartile range.

The given data set is

10,23,25,26,27,28,29,30,42,45.

So, this data set is ordered.

Taking it apart from the middle, the data values are

{10,23,25,26,27},{28,29,30,42,45}.

Now, the first quartile is the middle of the first set, ie. 25.

The third quartile is the middle of the second set, ie. 30.

So, the interquartile range is

=(30-25), ie. 5.

So, the length of the lower whisker is

=5*1.5

=7.5

So, the length of the lower whisker is 7.5.