conversations.from: human
conversations.value: Can you walk me through the solution of: Alex has some new shirts. Joe has 3 more new shirts than Alex. Ben has eight more new shirts than Joe. If Ben has 15 new shirts, how many new shirts does Alex have?
conversations.from: assistant
conversations.value: Joe has 15-8=7 new shirts.
  Alex has 7-3=4 new shirts.