The median is found by choosing the middle number after arranging all data from lowest-highest or highest-lowest.
The numbers rearranged in chronological order are:
5, 6, 7, 7, 9, 9, 10, 10, 12, 15
There are 10 numbers, meaning the median will be the average of the middle 2.
The middle 2 numbers are 9. Since they are the same, this makes the median 9.
