It really depends on the strength of the rest of your application. If you have a stellar GPA ( like 3.5 or higher), you might be able to get by with a 75% on your PCAT. If you only have a 3.0 though, the chances are a bit sketchier. You also will want to look at the strength of your extracurriculars and letters of recommendation, but generally a solid GPA base is what's needed.
Though 75% is within the range of most accepted applicants at your average pharmacy school ,I would retake it for the 80%+ score if your GPA is average or low.