3.11 Calculate the interquartile range (IQR) of the data. The interquartile range represents the middle 50 percent of the data, and is equal to the difference between the third 87 and Q3 = 109 (ac-...

In the attached image is a example for finding IQR. What I don’t understand is the significance of this number. What useful information about the distribution am I gaining by finding the IQR. Can you please give an example of how this information may be useful to a statistician or data scientist.

Extracted text: 3.11 Calculate the interquartile range (IQR) of the data. The interquartile range represents the middle 50 percent of the data, and is equal to the difference between the third 87 and Q3 = 109 (ac- and first quartiles. Recall that Q1 cording to Problems 3.8 and 3.10, respectively). IQR = Q3 - Q1 109 - 87 = 22 patient visits Note: Problems 3.8-3.12 refer to the data set in Problem 3.8, the number of patient visits per week at a chiropractor's office over a ten-week period.