This Problem Set is a part of the Lesson 15, Unit 8, Grade 6. Find the quartiles and interquartile range (IQR) of a data set, given a list of the values or a dot plot. Understand that the interquartile range is a measure of variability and that it can tell us about the distribution of data. Learning targets: students know what quartiles and interquartile range (IQR) measure and what they tell us about the data.