I'm sorry if its late but the answer is 21.5
If you arrange the numbers in order you will get this:
6,10,11,13,14,14,20,20,23,23,26,27,31,33,38,38
So, the two middle numbers are 20 and 23
Now, you have to add those 20+23=43
Then, you have to divide 43/2 and you'll get 21.5
Again sorry I'm late to responding