To find the interquartile range of a dataset, you first need to find the first quartile (Q1) and the third quartile (Q3).
To do this, you can arrange the dataset in ascending order: 11, 13, 14, 15, 17, 21, 22, 27.
Next, you can find the median of the lower half of the dataset (from 11 to 17). The median is 14.
Then, you can find the median of the upper half of the dataset (from 17 to 27). The median is 22.
Finally, you can calculate the interquartile range by subtracting Q1 from Q3: Q3 - Q1 = 22 - 14 = 8.
Therefore, the interquartile range of the given dataset is 8.