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Problem 4) Five coins are flipped. The first four coins will land on heads with probability...

Problem 4) Five coins are flipped. The first four coins will land on heads with probability 1/4. The fifth coin is a fair coin. Assume that the results of the flips are independent. Let X be the total number of heads that result.

(hint: Condition on the last flip).

a) Find P(X=2)

b) Determine E[X]

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