The following is quoted from the VMware Education site:
"Your exam may contain unscored questions in addition to the scored questions, this is a standard testing practice. You will not know which questions are unscored, your exam results will reflect your performance on the scored questions only.
VMware exams are scaled on a range from 100-500, with the determined raw cut score scaled to a value of 300. Scaled scoring allows for raw scores from different VMware exams to be scaled to a consistent value. Raw passing scores differ between VMware exams based on different technologies or different levels of competency. A scaled score provides a standard range for test takers and permits direct and fair comparisons of results ...