conversations.from: human
conversations.value: John adopts a dog from a shelter.  The dog ends up having health problems and this requires 3 vet appointments,  which cost $400 each.  After the first appointment, John paid $100 for pet insurance that covers 80% of the subsequent visits.  How much did he pay in total?
  Solve this problem.
conversations.from: assistant
conversations.value: He got a discount of 400*.8=$320
  He got that discount for 3-1=2 visits
  So each of those visits cost 400-320=$80
  So he paid 2*80=$160 for those visits
  That means he paid a total of 400+160+100=$660