conversations.from: human
conversations.value: Lily has 5 lottery tickets to sell.  She sells the first ticket for $1.  She then sells each successive ticket for a dollar more than the previous ticket. She plans to keep a $4 profit and give the remaining money as the prize. How much money will the winner of the lottery receive?
  Can you solve this problem?
conversations.from: assistant
conversations.value: The second ticket sold will cost $1 + $1 = $2.
  The third ticket sold will cost $2 + $1 = $3.
  The fourth ticket sold will cost $3 + $1 = $4.
  The fifth ticket sold will cost $4 + $1 = $5.
  The total money collected is $1 + $2 + $3 + $4 + $5 = $15.
  After taking profit, the total prize money will be $15 - $4 = $11.