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

Example Input: Problem: a train running at the speed of 70 km / hr crosses a pole in 9 sec . what is the length of the train ?
Example Output: 175 m

Example Input: Problem: a solution contains 8 parts of water for every 7 parts of lemonade syrup . how many parts of the solution should be removed and replaced with water so that the solution will now contain 25 % lemonade syrup ?
Example Output: 2.14

Example Input: Problem: a rectangular lawn of dimensions 80 m * 60 m has two roads each 10 m wide running in the middle of the lawn , one parallel to the length and the other parallel to the breadth . what is the cost of traveling the two roads at rs . 5 per sq m ?
Example Output:
6500