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

Example Input: Problem: a solution of 70 litres contains oil and water in the ratio 9 : x . if 6 litres of water is added to the solution , the ratio becomes 6 : 4 , find the value of x ?
Example Output: 

Example Input: Problem: ( 935421 x 625 ) = ?
Example Output: 584638125

Example Input: Problem: an error 2 % in excess is made while measuring the sideofa square . the % of error in the calculated area of the square is ?
Example Output:
4.04 %