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'.

Example Input: Problem: the average age of 15 students of a class is 15 years . out of these , the average age of 8 students is 14 years and that of the other 6 students is 16 years , the age of the 15 th student is 
Options: a ) 17 , b ) 12 , c ) 13 , d ) 14 , e ) 15
Example Output: a

Example Input: Problem: a , b and c started a business with a total investment of rs . 90000 . a invests rs . 6000 more than b and b invests rs . 3000 less than c . if the total profit at the end of a year is rs . 8640 , find b ' s share . 
Options: a ) rs . 2592 , b ) rs . 2520 , c ) rs . 2880 , d ) rs . 3360 , e ) none of these
Example Output: a

Example Input: Problem: the difference between the value of a number increased by 12.5 % and the value of the original number decreased by 25 % is 30 . what is the original number q ? 
Options: a ) 60 , b ) 80 , c ) 40 , d ) 120 , e ) 160
Example Output:
b