A courier records the delivery time, in minutes, of ten parcels dispatched on the same morning:
For the quartiles, use this convention: sort the data, split it at the median into a lower half and an upper half of equal size, and take and to be the medians of those two halves.
Compute the range and the interquartile range, then report .
Answer in minutes, rounded to the nearest whole minute.
Once you get it right, the reasoning behind the answer shows up here.
Visualize quartile construction, the middle 50%, outlier resistance, and box plots.
Dataset: [1, 2, 3, 4, 5, 6, 7]
Click Add Extreme Value (100) to see how Range and IQR respond differently when a very large observation is added to the dataset.