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

Example Input: Problem: what is the greatest prime factor of 2 ^ 10 - 1 ?
Example Output: 3

Example Input: Problem: a train covers a distance of 12 km in 10 minutes . if it takes 8 seconds to pass a telegraph post , then the length of the train is
Example Output: 160 m

Example Input: Problem: one night 17 percent of the female officers on a police force were on duty . if 204 police officers were on duty that night and half of these were female officers , how many female officers were on the police force ?
Example Output:
600