conversations.from: human
conversations.value: Shelby had $20 to take to the book fair. She bought one book for $8 and another for $4. She decided to buy as many $4 posters as she could with the money she had left. How many posters can she buy?
  Solve this problem.
conversations.from: assistant
conversations.value: She spent $8 + $4 = $12 on books.
  She started with $20, so she has $20 - $12 = $8 left to spend on posters.
  Each poster costs $4, so she can buy $8 / $4 = 2 posters.