Question

Suppose that on average 2 people in a major city die each year from alien attack. Suppose that each attack is random and independent.

(a) If X is the number of deaths from alien attack within the next year from a randomly selected major city, what type of random variable is X?

(b) Use the Poisson approximation to approximate the probability that the next major city you visit will have at least 3 deaths due to alien attack?

(c) Why do you think a Poisson approximation is being used?

Answer 1