The FE exam is not graded on a curve, and there is no guarantee that a certain percent of examinees will pass. Rather, NCEES uses a modification of the Angoff procedure to determine the suggested passing score. A committee of P.E/Phds examines each question and determines what fraction of minimally qualified engineers should be able to answer it. The summation of estimated fractions for all test questions becomes the passing score. It varies from year to year because of different questions. It is usually from 40-50%. Because the law in most states requires engineers to achieve a score of 70% to become liscensed, you may be reported as having achieved a score of 70 percent if your raw score is greater than the passing score established by NCEES regardless of the raw percentage.
Approximately 20% of each FE exam consists of questions repeated from previous examinatons--this is the equating subtest. Since the performance of previous examinees on the equating subtest is known, comparisons can be made between the two examinations and examinee populations. These comparisons are used to adjust the passing score.
If you can answer 30% of the test, guess 'c' for the rest (of which you will get 25% correct) chances are pretty good that you will pass. Also Jabberwocky, what state do you live in? No states I know about give a percent unless you fail. Additionally, (correct me if I'm wrong) I believe the just add E.I. on the business card.