Answer:
31
Step-by-step explanation:
The median is the number that we find in the middle of the data.
So if we have a sequence of {1,2,3}
Then 2 is the median
If we have a sequence of {1,2,3,4,5}
Then 3 is the median
We look in the middle of 28,30,30,30,30,31,31,31,31,31,31,31,31
and we find 31 in the middle.
Note:
If the middle is something with 2 terms in the middle like
1,2,3,4
Then the median is the average of the two middle terms which is
(2+3)/2 = 2.5