The free GMATPrep Software comes with 30 quant practice questions and some of these do repeat in the GMATPrep Practice tests. To show you the evidence, I have attached a screenshot of a problem that is part of the 30 practice questions and also part of the GMATPrep. My estimate is that around 7 of the 30 practice problems are also part of the GMATPrep practice test database. The test writers have been lazy and haven't really ensured that none of the 700 or so problems in the GMATPrep database appear anywhere else. In the past there was some overlap with the official guides as well. We are really at GMAC's mercy on this issue.
This is what I suggest, skip the 30 quant practice questions and don't attempt them prior to taking the free GMATPrep tests. Once you have taken the two tests then go on to practice with the Question Pack 1 and those 30 practice questions. The Question Pack 1 has no overlap with the questions in the GMATPrep free tests or the Exam Pack 1 tests.
Cheers,
Dabral
Attachments
GMATPrepProblemDuplicate.png [ 49.5 KiB | Viewed 2588 times ]
GMATPrepProblemPracticeProblem.png [ 54.37 KiB | Viewed 2573 times ]