Answer:
The interquartile range of the data set is 7.
Explanation:
The given set of data is
(18, 17, 10, 25, 20, 20, 30, 18, 18, 30, 25)
Arrange the data in ascending order.
10, 17, 18, 18, 18, 20, 20, 25, 25, 30, 30
Divide the data in two equal parts.
(10, 17, 18, 18, 18), 20, (20, 25, 25, 30, 30)
Divide each parenthesis in 2 equal parts.
(10, 17), 18, (18, 18), 20, (20, 25), 25, (30, 30)
Now we can say that,
Q1 = 18, Median = 20, Q3 = 25
Interquartile rage of a data is
I.Q.R. Q3 Q₁
I.Q.R.25-18=7
Therefore the interquartile range of the data set is 7.