This is the way I like to think of it:
let exam_scores = [100, 95, 60]
If ur rank second, ur SAC score will be exam_scores[2] = 95%.... Regardless of ur exam score.
So if u'r rank second. U will get the 2nd highest exam score as ur sac score. (Even if you got 60% or 100% on ur exam)
So u want ur cohort to do as well as possible on the exam!