Disclaimer: I could totally be wrong...but...

I believe if this is the same test as in America, there is no way to pass 100%. The 'CLEP' test is an assessment tool used to place you in the correct level of class/course in university based upon your current capability. For instance, depending on your score they may ask you to take pre-aglebra first, rather than heading straight into algebra. Another example: pre-calculus versus calculus.

I know that an english 'CLEP' exam also exists.

Good luck! You'll do fine :)