Unit 18 Section 3 : Measures of Central Tendency
Dispersion is how spread out a set of data are. One measure of dispersion is the range.
The range is the difference between the highest and lowest values in the data set.
Range = Highest Value  Lowest Value

Example
Look at this data:
The highest value is 22 and the lowest value is 3, so the range is 22  3.
The range of this data is 19
Example Questions
Work out the answer to the questions below then click
to see whether you are correct.
(a) What is the range of the data illustrated in the vertical line diagram on the right?
(b) Look at the values below.
5, 3, 2, 4, 6, 7, 9
What is the range of these data?
Exercises
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You have now completed Unit 18 Section 3
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Produced by A.J.Reynolds January 2001