answer: #Person2# books 5 flight tickets with a 10% discount.
documents: #Person1#: Excuse me, do you offer air flight reservation service here?
  #Person2#: Yes, is there anything I can do for you?
  #Person1#: I want to book tickets for Canada. How many flights are there each day?
  #Person2#: 4, at 6:30 am, 8 am, 2:30 pm and 6:30 pm.
  #Person1#: What's the airfare?
  #Person2#: 8000 Hong Kong dollars including security insurance.
  #Person1#: May I have any discount for 5 persons?
  #Person2#: Yes, 10%.
  #Person1#: OK, 5 tickets for the 6:30 pm flight.