Which set of population data is the least dispersed from its mean? 2, 3, 2, 9 4, 0, 4, 0 6, 2, 2, 2 9, 3, 5, 3.

Let x have probability generating function gx (s) and let un generating function u(s) of the sequence uo, u1, satisfies p(x > n). show that the (1- s)u(s) = 1 - gx(s), whenever the series defining these generating functions converge.