conversations.from: human
conversations.value: David and Dasha went to the carnival, where there are 9 rides.  Each ride costs 2 ride tickets at $2 per ticket.  You can also buy a ride bracelet for $30 which gives you 9 rides.  If David buys a ride bracelet and Dasha buys tickets, and they ride all 9 rides, how much money does David save?
  Give me a solution to this problem
conversations.from: assistant
conversations.value: Each ride cost 2 x $2 = $4.
  All 9 rides cost $4 x 9 = $36.
  By bathing the ride bracelet, David saves $36 - $30 = $6.