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

Input: Consider Input: Problem: a man , a woman and a boy can together complete a piece of work in 3 days . if a woman alone can do it in 6 days and a boy alone in 18 days , how long will a man take to complete the work ?

Output: 9 days


Input: Consider Input: Problem: in 1950 , richard was 4 times as old as robert . in 1955 , richard was 3 times as old as robert . in which year was richard 1.5 times as old as robert ?

Output: 200


Input: Consider Input: Problem: 4 , 12 , 48 , 240 , 1440 , 10080 , ( . . . )


Output: 80640