Answer:
Inter-quartile range = 3 .
Explanation:
Given : diagram with data.
To find : What is the inter-quartile range of the given data set.
Solution : We have given data .
We can see from the given data lowest value of data is 15 .
highest value of data = 21.
First quartile ( Q1) = 17
Second quartile (Q2) =18
Third quartile (Q3) = 20.
Inter-quartile range = Third quartile (Q3) - First quartile ( Q1) .
Inter-quartile range = 20 - 17
Inter-quartile range = 3 .
Therefore, Inter-quartile range = 3 .