Red Dragon asked:


I really need help with this:

Of all airline flight requests received by a certain discount ticket broker, 10% are for international travels and 90% are for domestic flights. Let X be the number of international flight requests of the next 20 customers. Assuming independence of successive requests, answer the following questions.
(1) What is the distribution of X? Give the name of the distribution and values of the parameters;
(2) List all the possible values of X;
(3) Compute the probability that P(X  5);
(4) Compute the mean and variance of X (using formulas).
(5) Interpret the mean you computed in (4).
(6) Compute the probability in (3) using Poisson approximation (ignore the condition np < 5 or nq < 5).

Brian