conversations.from: human
conversations.value: If you buy a dozen of doughnuts, it costs $8; but if you buy 2 dozens, it costs $14. How much will you save from buying 3 sets of 2 dozens than buying 6 sets of 1 dozen?
conversations.from: assistant
conversations.value: Six sets of 1 dozen of doughnuts cost $8 x 6 = $48.
  Three sets of 2 dozens of doughnuts cost $14 x 3 = $42.
  Therefore, you can save $48 - $42 = $6.