CrunchPrep’s full length practice tests are adaptive in nature, just like the GRE exam.
The GRE is a section adaptive exam, and so are the CrunchPrep tests. wherein the difficulty level of a section in the test is determined by your performance in the previous section.
Since there are two math and two verbal sections, the difficulty of questions in the second section in each math and verbal depends on how you perform on the first sections.
Your final scaled scored depends on how many questions you got right, along with the difficulty level of the sections. CrunchPrep's algorithm works exactly the same, and you'll get a very accurate score prediction at the end of the test so you can measure your performance easily.