Pamela,
Here are a few considerations regarding the pretest questions and the percentages:
PMI doesn't actually disclose how they do this. My best guess is that the pretest questions are excluded and that the percentages are calculated for the questions on which you will actually be scored on.
However... during the exam you will NOT know which ones are or are not pretest questions. All you will see is a question with four answers. You don't know which domain it is from, and even if you think that it's from "Planning" does that match what PMI considers it to be? Maybe PMI thinks that it's Executing? Who knows?
Lastly, in The PM Exam Simulator, we are calculating the percentages based on the total number of questions in the exam. There are NO pretest questions in our exams. But that doesn't mean that you can now simply go and 'dismiss' 25 of the questions you had wrong as "pretest" questions. It simply means that you answered those 25 questions wrong and that you should review why and study on those topics, so that you can answer similar questions on the real exam correctly.
Until Next Time,
Cornelius Fichtner, PMP, CSM
President, OSP International LLC