Question

This box plot shows the distribution of

the numbers of legs on some
centipedes.
Work out the range and the
interquartile range of the numbers of
legs.
40
80
Number of legs
120

Answer 1

The range and the interquartile range of the numbers of legs include;

Range = 60 legs.

Interquartile range (IQR) = 44 legs.

In Mathematics and Statistics, the range of a data set can be calculated by using this mathematical expression;

Range = Highest number - Lowest number

Note: Each interval on the box plot axes represents 4 units.

Range = 104 - 44

Range = 60 legs.

In Mathematics and Statistics, IQR is an abbreviation for interquartile range and it is a measure of the middle 50% of data values when they are ordered from lowest to highest.

Mathematically, interquartile range (IQR) of a data set is the difference between third quartile and the first quartile:

Interquartile range (IQR) of data set = third quartile - first quartile

Interquartile range (IQR) of data set = 96 - 52

Interquartile range (IQR) of data set = 44 legs.