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

Example Input: Problem: the s . i . on a certain sum of money for 2 years at 8 % per annum is half the c . i . on rs . 4000 for 2 years at 10 % per annum . the sum placed on s . i . is ?
Example Output: 262

Example Input: Problem: three 7 faced dice are thrown together . the probability that all the three show the same number on them is ?
Example Output: 1 / 49

Example Input: Problem: jaylen was planning to save all summer for a pair of jordan 12 s . they cost $ 250 . jaylen figured that he could cut grass to help with the cost of the sneakers . how many yards would jaylen have to cut if he charges $ 2.15 per yard ?
Example Output:
115.74 yards