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

Example Input: Problem: if a = 105 and a ^ 3 = 21 × 25 × 45 × z , what is the value of z ?
Example Output: 49

Example Input: Problem: by selling an article at rs . 600 , a shopkeeper makes a profit of 25 % . at what price should he sell the article so as to make a loss of 25 % ?
Example Output: s . 360

Example Input: Problem: the length of a train and that of a platform are equal . if with a speed of 36 k / hr , the train crosses the platform in one minute , then the length of the train ( in meters ) is ?
Example Output:
300