The median is 6.5.
The first quartile is 5.
The third quartile is 8.
The interquartile range is 3.
The numbers in the dot plot are: 4, 4, 4, 4, 5, 5, 6, 6, 6, 6, 7, 7, 7, 8, 8, 8, 9, 9, 9, 22
Median is the number in the middle of the dataset.
Median = 1/2 ( n + 1)
1/2 x 21 = 11.5th number = (6+ 7) / 2 = 6.5
First quartile = 1/4 x (n + 1)
1/4 x 21 = 5.25th number = 5
Third quartile = 3/4 x (n + 1)
3/4 x 21 = 15.75th number = 8
Interquartile range = 8 - 5 = 3
Please find attached the dot plot. To learn more about interquartile range, please check: https://brainly.com/question/3966385
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