conversations.from: human
conversations.value: Provide a step by step solution for the following math problem: Vincent's bookstore is divided into different kinds of books. His top-selling books are fantasy books. He also sells literature books which cost half of the price of a fantasy book. If his fantasy books cost $4 each, and he sold five fantasy books and eight literature books per day, how much money will he earn after five days?
conversations.from: assistant
conversations.value: Vincent earns $4 x 5= $20 for selling 5 fantasy books per day.
  The price of the literature book is $4/2 = $2 each.
  He earns $2 x 8= $16 per day for selling 8 literature books.
  So the total money he earns per day is $16 + $20= $36.
  Therefore, he will earn $36 x 5= $180 after 5 days.