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

Ex Input:
Problem: 12 men work 8 hours per day to complete the work in 10 days . to complete the same work in 8 days , working 15 hours a day , the number of men required ?

Ex Output:
8 days


Ex Input:
Problem: the cost of the paint is rs . 50 per kg . if 1 kg of paint covers 20 sq . ft , how much will it cost to paint outside of a cube having 20 feet each side

Ex Output:
rs . 6000


Ex Input:
Problem: arnold and danny are two twin brothers that are celebrating their birthday . the product of their ages today is smaller by 15 from the product of their ages a year from today . what is their age today ?

Ex Output:

7 .