My advice to you is DO NOT predict your LSAT score. Unless you have taken several previously adminstered LSAC practice exams under realistic test conditions and have been consistently getting between a 155 and 160 then all you are doing is shooting yourself in the foot by assuming you will get a certain score.
If you have not taken practice tests and/or studied extensively then I would recommend signing up for a prep course (Kaplan and Princeton Review are both very reputable).
I tell you this because I speak from experience. I also went to UMass-Amherst and graduated with a 3.5 GPA. I assumed that because I did well in school and did well on the SAT that I would do fine on the LSAT as well. WRONG ANSWER!
I went in to the LSAT completely blind. I didn’t even know what the test conisted of and it certainly showed. I took a prep course and studied alot and my score went up considerably. Unfortunately your LSAT score is kept on file for 5 years and multiple scores are averaged.
