With 1026 being the mean score on the SAT and StDev of 209, Jessica has a score of 799/209 z-scores above the mean. Her z-score would be 3.823. The mean of the ACT and StDev are 20.8 and 4.8, respectively. A 28 ACT score would be 7.2/4.8 z-scores above the mean, for a z = 1.500. This means that Jessica has the higher z-score.