Answer: 13.5
Order the numbers
Before: 14, 9, 20, 5, 17, 13
After: 5, 9, 13, 14, 17, 20
Put your left pointer finger on 5 and your right pointer finger on 20. Move your left to the right until it goes to 13 and move your right to the left until it goes to 14.
The middle number is 13.5 so 13.5 is the median.