conversations.from: human
conversations.value: Find a solution for this math problem: Rachel earned $200 babysitting. She spent 1/4 of the money on lunch. She spent 1/2 of the money on a DVD. How much did Rachel have left?
conversations.from: assistant
conversations.value: Rachel spent 1/4*200 = $50 on lunch.
  Rachel spent 1/2*200 = $100 on a DVD.
  Rachel has 200-50-100 = $50 left.