PACKRAT is scored out of 225 questions, so obtaining a 140 = 62%. Request the results which also include keyword feedback to highlight what a PACKRAT taker got wrong. If your program is not releasing results to you but only providing a score then that is not helpful. Good goal is to be above national mean for your form which the results will outline. There are 2 forms used every year, current year and preceding. In those results, you will find comparison to class and national mean for the form of the exam.
Your program can release the results to you from PACKRAT.