answer: #Person1# buys four chocolate bars with tax included from #Person2#.
documents: #Person1#: Excuse me. How much is the chocolate bar? 
  #Person2#: One dollar. 
  #Person1#: So, I can have five for five dollars? 
  #Person2#: Actually, you can only have four. 
  #Person1#: Oh, yeah. I forgot tax. Give me four then, please. 
  #Person2#: Okay. Thanks.