Harrigan University is a liberal arts university in the midwest that attempts to attract the highest-qulaity students. It has gathered data on 178 applicants who were accepted by Harrigan (a random sample from all acceptable applicants over the past several years)

Using excel, Calculate a 95% confidence interval for the proportion of all acceptable applicants who accept Harrigan's invitation to enroll. Do the same for all acceptable applicants with a combined score less than 330, with a combined score between 330 and 375, and then with a combined score greater than 375. (Note that 330 and 375 are approximately the first and third quartiles of the Combined Score variable)

I've done the first portion of the question but I need help on the second part. Can you tell me if I'm supposed to use the sample size of all the applicants or just the calculation of less than 330 to calculate the confidence interval?