The PMP® Certification Exam is comprised of 200 MCQs, out of which 175 are scored questions and rest 25 are unscored questions.
You have to solve all these questions within 4 hours. And since there is no negative marking, I would suggest you attempt each and every question, even if you are not sure about the correct answer.
There is no fixed score to clear the PMP® exam.
The marks you obtain will be based on the difficulty level of the questions you get. PMI follows such a format because the PMP® certification exam is a psychometric test. In this, no two candidates get the same set of questions nor all the questions carry equal weightage. If you get a questionnaire with easy questions, then the passing score is likely to be higher for you. Similarly, if you get difficult questions, then the passing score will be much lower.
For more info refer to https://www.edureka.co/blog/pmp-exam-all-you-need-to-know/#pmpformat