Start with three numbers, say 5, 17, and 23. Their median (middle value) is 17. Find a fourth number so that the mean of all four is 17. This number must be 23 (4 x 17 – 5 – 17 – 23).
Repeat the process. The median of 5, 17, 23, and 23 is halfway between 17 and 23 (20).
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