conversations.from: human
conversations.value: A football club has a balance of $100 million. The club then sells 2 of its players at $10 million each, and buys 4 more at $15 million each. How much money is left in the club register in millions of dollars?
  Solve this problem.
conversations.from: assistant
conversations.value: The 2 players are sold for a total of 2*10 = $20 million
  So the club has 100 + 20 = $120 million
  The cost of buying 4 more players at $15 million each is 4*15 = $60 million
  So the club now has 120 – 60 = $60 million