Suppose a Flu Epidemic Is Sweeping a Campus and Many

Multiple Choice

Suppose a flu epidemic is sweeping a campus and many students are sick. Student health services finds that 30% of students are ill. A nurse samples a dormitory with 30 students and wants to calculate the probability that at least 10 students are sick. Which of the following statements is false?

A) The binomial distribution cannot be used in this example, because the probability that 1 student is sick is not independent of another student in the dorm also being sick.
B) The Normal approximation to the binomial cannot be used, because the binomial distribution is not an appropriate model.
C) The Normal approximation to the binomial could not be used, even if the binomial were an appropriate model, because np = 30 × 0.3 = 9 and this violates one criterion for using the Normal approximation.
D) The binomial distribution can be used here, because our variable of interest is a finite count with minimum 0 and maximum 30.