We also conduct a hypothesis test with this data and find that students who retake the sat without prepit! also do significantly better (p-value < 0.0001). so now we want to determine if prepit! students improve more than students who retake the sat without going through the prepit! program. in a hypothesis test, the difference in sample mean improvement (“prepit! gain” minus “control gain”) gives a p-value of 0.004. a 90% confidence interval based on this sample difference is 3.0 to 13.0. what can we conclude?