Answer: C) 11.5
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Step-by-step explanation:
When finding the median, the first task is to sort the values from smallest to largest (aka sort in ascending or increasing order).
The given set
{10, 19, 20, 13, 13, 2, 10, 8, 25, 10}
sorts to
{2, 8, 10, 10, 10, 13, 13, 19, 20, 25}
Because there are n = 10 people in this set, this means the middle value is between slot n/2 = 10/2 = 5 and slot 6.
The values in slots 5 and 6 are 10, 13 in that exact order.
We'll add those values up, and divide by 2 to get the midpoint
(10+13)/2 = 23/2 = 11.5 which is the median.
This trick of "add them up, divide by 2" only applies if n is even.