Ariyo,
The Pass/Fail demarcation for any professional exam is a closely guarded secret at the professional organization (in this case, PMI). This is for a number of reasons, but the biggest one is that the pass/fail line changes somewhat from test to test. Professional certification exams are not a all like tests in school where the instructor sets a solid mark, above which is "pass" and below which is "fail."
Modern professional certification exams have a "question bank" with 2000-10,000 questions, depending on the certification. All of these questions are vetted so there is little-to-no question as to the "right answer" (or the answer the certifying body is looking for.) When you sign in to the exam you will receive a random sampling of the questions from the bank. Note - in PMI's case, there will be a very small number of questions that EVERYONE will see (like 20 or 25) - this is done for quality assurance purposes. The passing score will be some derived number based on the which questions you get from the bank, but will vary from test to test.
The best advice the mods can give is this: If you are scoring 80%+ on full exams on the simulator, you PROBABLY will do OK on the exam - but there are no guarantees about that.
Best of luck,
Harry
+++++
Harry J. Elston, Ph.D., CIH, PMP