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3. Suppose X is a Bernoulli random variable with unknown parameter p 6 (0,1), and that we want to take a random sample of size n large enough so that the 90% condence interval has maximum error of the estimate 5 = 0.2. Find suitable it under the following scenarios. (a) 4 You have no knowledge about the value of p. (b) ' _ . You are certain that p 2 0.8. Hint. Sketch a graph of f (p) = p(1 p) and see that you have a bound for p(1 p)