Hey xluux.

As a hint to start off you will need to use either statistical tables or a computer to do the calculations for the Binomial probabilities for P(X = x) with n = 15, p = 0.8 and x = 0 to 15 by adding up all P(X = x) terms in that question.

Have you covered the calculation of the Binomial in class using either statistical tables or a computer?