The average age of 15 students of a class is 15 years. Out of these, the average age of 4 students is 14 years and that of the other 9 students is 16 years. Tee age of the 15th student is?  Choices:
A) 20 years B) 22 years C) 24 years D) 25 years E) 27 years

Rationale: "age of the 15 th student = [ 15 * 15 - ( 14 * 4 + 16 * 9 ) ] = ( 225 - 200 ) = 25 years . answer : d"
Answer: D