Answer:
8
Step-by-step explanation:
The interquartile range of a data set is the difference between the upper and lower quartiles.
First, put the values in order from least to greatest:
8, 9, 9, 9, 10, 11, 13, 15, 17, 18, 22
To find the upper quartile, we need to first find the median.
The median of this data set is 11, because it is in the middle of the values.
The upper quartile is the median of all the numbers to the left of 11.
The median of 8, 9, 9, 9, and 10 is 9, because it's in the middle.
So the upper quartile is 9.
The lower quartile is the same, but to the right of 11. The median of 13, 15, 17, 18, and 22 is 17 because it's in the middle.
Now, to find the interquartile range, find the difference between 18 and 9.
17 - 9 = 8
