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

Example Input: Problem: a cycle is bought for rs . 900 and sold for rs . 1080 , find the gain percent ?
Example Output: 20 %

Example Input: Problem: of 30 applicants for a job , 9 had at least 4 years ' experience , 18 had degrees , and 3 had less than 4 years ' experience and did not have a degree . how many of the applicants had at least 4 years ' experience and a degree ?
Example Output: 10

Example Input: Problem: the diagonal of a rhombus are 70 m and 160 m . its area is :
Example Output:
5600