conversations.from: human
conversations.value: Michelangelo has 28 ceilings to paint. This week, he paints 12 of them. Next week, he will paint 1/4 the number of ceilings he did this week. How many ceilings will be left to paint after next week?
  Solve it.
conversations.from: assistant
conversations.value: After this week, Michelangelo will have 28-12=16 more ceilings to paint.
  Next week, Michelangelo will paint 12/4=3 ceilings.
  Michelangelo will have 16-3=13 more ceilings to paint.