question_answer

Two rows of numbers are given. The resultant number in each row is to be worked out separately based on the following rules and the question below the rows of numbers is to be answered. The operation on numbers progresses from left to right. Rules: If an odd number is followed by another composite odd number, they are to be multiplied. If an even number is followed by an odd number, they are to be added. If an even number is followed by a number which is a perfect square, the even number is to be subtracted from the perfect square. If an odd number is followed by an even number, the second one is to be subtracted from the first one. If an odd number is followed by a prime odd number, the first number is to be divided by the second number.

27	18	3
21	x	9

If x is the resultant of the first row, what will be the resultant of the second row?                                                          (SOF IMO 2016)

A) 63                                

B) 36            

C) 3                                 

D) 16