instruction:
The task is to generate the correct answer for a given math problem.
question:
Problem: the sum of the even numbers between 1 and n is 89 * 90 , where n is an odd number , then n = ?
answer:
179


question:
Problem: the total age of a and b is 12 years more than the total age of b and c . c is how many year younger than a
answer:
12


question:
Problem: two bullet trains of equal lengths take 10 seconds and 12 seconds respectively to cross a telegraph post . if the length of each bullet train be 120 metres , in what time ( in seconds ) will they cross each other travelling in opposite direction ?
answer:

11 sec .