conversations.from: human
conversations.value: Break down this math problem: John is raising money for a school trip. He has applied for help from the school, which has decided to cover half the cost of the trip. How much money is John missing if he has $50 and the trip costs $300?
conversations.from: assistant
conversations.value: John's school has decided to pay 300 / 2 = $150 for his trip.
  In total John has covered 150 + 50 = $200 for his trip
  Therefore, John needs 300 - 200 = $100 more for the trip.