conversations.from: human
conversations.value: Lisa has 18 more dresses than Ana. If the number of their dresses combined is 48, how many dresses does Ana have?
  Solve it.
conversations.from: assistant
conversations.value: If Lisa's surplus of 18 dresses is taken away from the total, they will have 48-18 = 30 dresses in total
  They would each have the same number of dresses from these 30 i.e. 30/2 = 15 dresses which is the number of dresses that Ana actually has.