String theory. Suppose that the expected number of students who take String Theory is 23, with variance 169. Suppose that the assigned classroom can hold only 40 students. Also, 6 students is the minimum enrollment, i.e., if 5 or less people sign up, the class will be combined with another. What is a bound on the probability that the class is held (i.e., has a sufficient number of students) and can be taught in the intended classroom (i.e., does not have too many students)?