conversations.from: human
conversations.value: I'm completely lost with this math problem: John sublets his apartment to 3 people who each pay $400 per month.  He rents the apartment for $900 a month.  How much profit does he make in a year?
  Can you give me a hand?
conversations.from: assistant
conversations.value: He gets 3*$400=$1200 per month
  So he gets 1200*12=$14,400 per year
  So he pays 12*900=$10800 a year
  That means his profit is 14400-10800=$3600 per year