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One thousand independent flips of a fair coin are made. Let X denote the number of heads obtained
(1) find the probability distribution function of the random variable X.
(2) Find the probability that at least one head appears, P(X>=1)
(3)Find E(X)and Var(X)
(4) Let Z=X-E(X)/根号Var(X).Assume that Z follows the standard normal distribution.Given the assumption, compute P(X>=1).Compare (4)with(2)

[此贴子已经被作者于2008-4-21 13:16:17编辑过]