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

Example Input: Problem: a train running at the speed of 40 km / hr crosses a pole in 9 seconds . what is the length of the train ?
Example Output: 100 meter

Example Input: Problem: the average of first 10 odd numbers is ?
Example Output: 10

Example Input: Problem: a cycle is bought for rs . 900 and sold for rs . 1170 , find the gain percent ?
Example Output:
30 %