conversations.from: human
conversations.value: I would love to understand how to solve this problem: James gets 10 new CDs.  Each CD cost $15.  He gets them for 40% off.  He decides he doesn't like 5 of them and sells them for 40. How much money was he out?
  Can you explain?
conversations.from: assistant
conversations.value: He got a 15*.4=$6 discount on each CD
  That means each CD cost 15-6=$9
  So he paid 10*9=$90
  That means he was out 90-40=$50