conversations.from: human
conversations.value: At a station, a train comes every 5 minutes leaving 200 passengers and taking 320 others. How many different passengers step on and off a train at the station within an hour?
  Find the solution.
conversations.from: assistant
conversations.value: At every passenger exchange there are 200 + 320 = 520 different people.
  One hour is 60 minutes, so during one hour, a train comes 60 minutes/hour / 5 minutes/train = 12 times.
  So during one hour, 12 trains * 520 passengers/train = 6240 different passengers step on and off the train.