A Poisson distribution is such that the probability is the same for X = 1 and X = 2. What is this probability? Solution Note that for a Poisson distribution, P(x) = u^x e^(-u)/x! Thus, P(0) = e(-u) P(1) = u (e^-u) Thus, u(e^-u) = e^(-u) e^(-u) (1-u) = 0 Thus, u = 1 Thus, P(0) = P(1) = e^(-1) = 0.367879441 [ANSWER].