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

Example Input: Problem: a jar contains a mixture of ab in the ratio 4 : 1 . when 40 l of mixture is replaced with liquid b , ratio becomes 2 : 3 . how many liters of liquid a was present in mixture initially .
Example Output: 64

Example Input: Problem: the cross - section of a cannel is a trapezium in shape . if the cannel is 8 m wide at the top and 6 m wide at the bottom and the area of cross - section is 700 sq m , the depth of cannel is ?
Example Output: 100

Example Input: Problem: how many different positive integers exist between 10 ^ 5 and 10 ^ 6 , the sum of whose digits is equal to 2 ?
Example Output:
6