Median (statistics)

Definition

The median of a set of numbers is the middle element in a set when the elements are written in order (i.e. least to greatest). When the number of elements is even, there are two middle elements and so the average of the two is taken to be the median. These show up frequently on contest problems, and also in statistics. For example, to find the median of the set {5, 3, 9, 7}, we would first write it in order {3, 5, 7, 9}. Then, to find the median, we take

Problems

Find the median of {3, 4, 5, 15, 9}.

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