I want to share with everyone the video explanations to all of the problems in the quantitative section of the GMAT Paper Tests. The overlap with the Official Guides is color coded. There are about 450 problems.http://www.gmatquantum.com/gmat-paper-tests/
The GMAT Paper Tests are "retired" GMAT tests conforming to the old format of the test. The questions are on the easier side but here are some use for these paper tests:
1. Good practice for students who have difficulty grasping the basic concepts and is a good introductory exposure to GMAT's language and style.
2. Useful for students who make a lot of arithmetic and careless mistakes and get tripped on easy/medium questions.
3. Students looking for somewhat harder problems can also selectively focus on the harder questions that are concentrated toward the end of each section.
Free Video Explanations: OFFICIAL GUIDE GMAT 13, 12, 11, 10; QUANT REVIEW 2nd, 1st.