You should simply calculate your raw percentage for the Peterson exams. This will let you know how well you did on the exam. However, the actual CLEP exams are scored using a formulaic grading scale. So there is no direct correlation between a score of 75% on a Peterson's exam, and a score of '75' on a CLEP exam. This lack of parity is made more obvious when you consider a score of 95% on a Peterson's exam. Since scores on CLEP exam can only be between 20 and 80, there is no way to directly compare the two scores.

We can, however, observe a very general relationship between a midline score of 50 on a CLEP and a 50% on a Peterson's. In general, you should aim to score as far above 50% on the Peterson's mock exams as possible. The higher you score above 50%, the more likely it is you will pass the actual CLEP (though it's by no means guaranteed).

Hope that helps,
Snazzlefrag

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My name is Rob
So far, I have earned 139 credits (12 not used).

Excelsior College
- BS Psychology (15 credits - 5 courses/exams to go)
- BS Business (9 credits - 3 courses/exams to go)
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Upcoming: An UL business course of some kind.
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Exams/Courses Passed To Date (42):
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- Exams (39): 24 DANTES, 15 CLEP.