Range

In a Nutshell

The range measures how spread out the data is: range=largest value−smallest value\text{range} = \text{largest value} - \text{smallest value}.

The range is not an average — it is a measure of spread. It tells you the gap between the highest and lowest values in a data set.

Range=maximum−minimum\text{Range} = \text{maximum} - \text{minimum}

A small range means the data values are close together (consistent). A large range means the data is spread out (varied).

For example, test scores of 55,62,58,60,5755, 62, 58, 60, 57 have a range of 62−55=762 - 55 = 7 marks — fairly consistent. But scores of 23,95,41,88,6723, 95, 41, 88, 67 have a range of 95−23=7295 - 23 = 72 marks — very spread out.

Averages and range visualiser A dot plot showing each data value. Annotations mark the mean, median, mode and range on the diagram.

Watch it work

Question: The temperatures (°C) over a week were 12,8,15,9,14,11,712, 8, 15, 9, 14, 11, 7. Find the range.

Have a go

Q1. Find the range of 3,9,1,7,53, 9, 1, 7, 5.

Q2. The range of a data set is 15. The smallest value is 22. What is the largest value?

Q3. Two football teams have these scores over 5 matches. Team A: 1, 2, 1, 3, 2. Team B: 0, 5, 1, 4, 0. Which team is more consistent?

Q4. A data set is 4,4,4,4,44, 4, 4, 4, 4. What is the range? What does this tell you?