For example, to maintain a consistent standard for success, a new version of an exam, which contains more dificult questions than the prior version will be assigned a somewhat lower required passing score. For this reason, passing scores may vary between different exams in your certification track, and between later and earlier versions of the same exam.
Oracle says that if the exam is difficult then required passing score will be low with compare to other exams.That's not what the text says, what it says is: "...a new *version* of an exam, which contains more difficult questions than the *prior version* will be assigned a somewhat lower required passing..."
Any idea why there is a difference in pricing and also passing score.1Z0-051 is available online (i.e. not proctored). It is cheaper because that method costs Oracle less to offer. My opinion is that it vastly reduces the value of passing it because it is too easy to cheat, but that's a completely different topic.
And also suggest me which test I need to attend.I wrote an article a few months ago discussing the two tests and why you might take one over the other: