conversations.from: human
conversations.value: John is twice as old as Mary and half as old as Tonya. If Tanya is 60, what is their average age?
  Give me a detailed solution.
conversations.from: assistant
conversations.value: John is 30 because 60 / 2 = 30
  Mary is fifteen because 30 / 2 = 15
  Their total age is 105 because 60 + 30 + 15 = 105
  Their average age is 35 because 105 / 3 = 35