conversations.from: human
conversations.value: This math problem has got me stumped: Elizabeth has 20 dollars and wants to buy pens and pencils. Each pencil costs $1.60 and each pen cost 2 dollars. How many pencils can she buy with her 20 dollars if she wants 6 pens?
  Can you show me the way?
conversations.from: assistant
conversations.value: Elizabeth spends 6*2 = 12 dollars on pens.
  Elizabeth has 20-12 = 8 dollars to spend on pencils.
  Elizabeth can buy 8/1.6 = 5 pencils.