Set S consists of integers {8, 11, 12, 14, 15}. If integer n is included in the set, the average (arithmetic mean) of set S will increase by 25%. What is the value of integer n?  Select.
A) 28
B) 32
C) 36
D) 40
E) 44

Rationale: the average of the numbers in set s is 12 . if we increase the mean by 25 % , the new mean is 15 . thus , on average , 5 numbers increase by 5 . therefore n = 15 + 25 = 40 the answer is d .
Answer: D