Answer:
12
Step-by-step explanation:
As there are 7 values in the given set, and one is missing, then the full set comprises 8 values.
2,7,8,14,15,20,29.
The middle value is 14 so we need another value, v such that, ½(14 + v) = 13.
This solves as v = 12.
The full set now is,2,7,8,12,14,15,20,29.
