8/31/2014 The heights of U.S. adult males is approximately Normal with a mean of 69in and a standard deviation of 2.5in. If 1200 U.S. adult males are randomly selected, how many would be expected to lie exceed 70.5in?

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8/31/2014 Solution. If X is a random variable denoting the heights of U.S. adult men in inches, X ~ N(69, 2.5). We first need P(X > 70.5). Directly using the graphing calculator, P = NormalCdf(70.5, 9999, 69, 2.5) = 0.2742. [We could also get the same results by finding the Z-score corresponding to 70.5in, Z = 0.6 and then use tables. Required, N = 0.2742*1200 = 329.1