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

Ex Input:
Problem: a person want to give his money of $ 1800 to his 3 children a , b , c in the ratio 2 : 3 : 4 . what is the b ' s share ?

Ex Output:
$ 600


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

Ex Output:
20 %


Ex Input:
Problem: two trains of length 100 m and 200 m are 100 m apart . they start moving towards each other on parallel tracks , at speeds 36 kmph and 72 kmph . in how much time will the trains cross each other ?

Ex Output:

40 / 3