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

[EX Q]: Problem: how much interest will $ 10,000 earn in 9 months at an annual rate of 4 % ?
[EX A]: $ 300

[EX Q]: Problem: the sum of the even numbers between 1 and n is 89 * 90 , where n is an odd number , then n = ?
[EX A]: 179

[EX Q]: Problem: a 120.00001 metres long train running at the speed of 120 kmph crosses another train running in opposite direction at the speed of 80 kmph in 9 seconds . what is the length of the other train ?
[EX A]:
380 meter