Problem 2. Dodson, Williams, and their horse Bolivar want to get from city A to city B as quickly as possible. Along the road, there are 27 telegraph poles that divide the entire journey into 28 equal segments. Dodson takes 9 minutes to walk one segment, Williams takes 11 minutes, and either of them can ride Bolivar to cover the distance in 3 minutes (Bolivar cannot carry both). They set out from city A simultaneously; the journey is considered complete when all of them arrive in city B.

They agreed that part of the way Dodson will ride, then tie Bolivar to one of the telegraph poles and continue on foot, while Williams will initially walk and then ride Bolivar. At which pole should Dodson tie Bolivar to minimize the travel time to city B?

Answer: at the 12th, counting from A.