I truly doubt that the pass mark for exams would be 100%. Usually it is 80, although they will always say that you should 'strive for 100%', but it can't possibly be the pass mark. People would never get through ground school if it were. I know people who have flown for 20 years on heaps of different aircraft types and average in the upper nineties on their exams.
I just did a Qantaslink groundschool and the pass mark was 80%. I've flown before and still only managed one 100% on one of my exams. The rest in the upper nineties.