The task is to generate the correct answer for a given math problem.

Ex Input:
Problem: a 10 % stock yields 8 % . the market value of the stock is :

Ex Output:
rs . 125


Ex Input:
Problem: if 5 a = 3125 , then the value of 5 ( a - 3 ) is :

Ex Output:
25


Ex Input:
Problem: a can finish a work in 18 days and b can do the same work in half the time taken by a . then , working together what part of the same work they can finish in a day ?

Ex Output:

1 / 6