In this task, you need to answer the given multiple-choice question on the general math. Classify your answers into 'a', 'b', 'c', 'd', and 'e'.

Input: Consider Input: Problem: if 5 x = 6 y and xy ≠ 0 , what is the ratio of 1 / 3 * x to 1 / 5 * y ? 
Options: a ) 25 / 6 , b ) 36 / 25 , c ) 2 , d ) 5 / 6 , e ) 25 / 36

Output: c


Input: Consider Input: Problem: if xy > 0 , 1 / x + 1 / y = 4 , and 1 / xy = 6 , then ( x + y ) / 2 = ? 
Options: a ) 1 / 25 , b ) 1 / 6 , c ) 1 / 5 , d ) 1 / 3 , e ) 6

Output: d


Input: Consider Input: Problem: the average of 5 quantities is 9 . the average of 3 of them is 4 . what is the average of remaining 2 numbers ? 
Options: a ) 16.5 , b ) 10 , c ) 8 , d ) 9.5 , e ) none of these


Output: a