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

Input: Consider Input: Problem: calculate the sum of first 60 natural numbers .

Output: 1830


Input: Consider Input: Problem: a number x is mistakenly divided by 10 instead of being multiplied by 10 . what is the percentage error in the result ?

Output: - 99 %


Input: Consider Input: Problem: a train which has 430 m long , is running 45 kmph . in what time will it cross a person moving at 9 kmph in same direction ?


Output: 43 sec