What is the interquartile range of this data?
6
7
8
9

The interquartile range of this data is:

                                   8

From the box plot given to us we see that:

Minimum value of the set is: 18

The first quartile or the lower quartile of the set i.e.

The middle quartile or the median of the set i.e.

The upper quartile or third quartile i.e.

Maximum value of the set is: 42

Hence, the interquartile range of the data is:

             Hence, the interquartile range is: 8

Option d) an irrational number

Step-by-step explanation:

When a rational number and an irrational are added the result cannot be a terminating decimals because the sum cannot be a rational number hence cannot be terminating decimal.

b) cannot be correct when a rational number is added with irrational number

we cannot get rational number at all.

c) Fraction is also one part of rational hence not possible

d) an irrational number is correct choice.