In statistics, it is imperative to arrange your data entries from least to greatest. That would be the first step of our solution
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Interquartile range is the difference of the last quartile to the first quartile. Divide your entire data set into four parts. Each division is called a quartile. Its numerical value is the average of its numbers. However, since our data set contains 7 numbers, which is odd, we write the median (middle value) twice. The quartiles are: