Answer:
15
Explanation:
The median, is just the middle number in a set of numbers.
In this case, our set is: 17, 8, 15, 21, 12.
However, the set must be in increasing order, so the set becomes: 8, 12, 15, 17, 21.
This gives us the median, which is the middle number, to be: 15.
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