answer with explanation

The grand cooking school of Tarator offers the three courses Riba. Meso and Sladki. Applicants choose one of the three courses to apply for and there always are a very large number of applicants to all three courses. (a) Assume that Tarator admits a total of n = 33 students and that the proportion of applicants applying to each of the three courses is the same. What is the probability that each course has exactly the expected number of participants given that participants are selected with equal chances of admission independently of their chosen course? [3]