conversations.from: human
conversations.value: James has 18 chocolate bars to sell for the swim team. He sold 5 last week and 7 this week. How many more chocolate bars does he need to sell?
conversations.from: assistant
conversations.value: He has sold a total of 5 + 7 = 12 chocolate bars so far.
  James needs to sell 18 - 12 = 6 more chocolate bars.