Here’s another set of video explanations (one math, one verbal) of practice problems found in ETS’s Paper-based Practice Test for the Revised GRE, a PDF released by the test-makers themselves.
You can find the whole set of explanations for every practice problem here. Enjoy!
Verbal: Section 3, Question #22 on page 57: an RC question on the passage about brain processes that begins, “The author of the passage mentions the classical conception of free will primarily in order to…”
Math: Section 5, Question #22 on page 79 that begins: “If c and d are positive integers and m is the greatest common factor of c and d, then m must be the greatest common factor of c and….”