Notes: Finding Quartiles & Interquartile range in a Data Set

interquartile range (IQR) is the spread of the middle 50% of the data values. So: The interquartile range is a more useful measure of spread than the range as it describes the middle 50% of the data values. Example. Find the median, lower quartile, upper quartile and interquartile range of the following data set of scores: ................
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