Question 1118357
the mean is np = 66 * 0.053 = 3.498
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standard deviation = square root(np(1-p)) = square root(3.498 * (1-0.053)) = 1.8201
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a) Probability (P) (X>6) = 1 - P(X<=6) 
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z-score(X<=6) = (6-3.498)/1.8201 = 1.3746 approximately 1.37
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P(X<=6) = 0.9147
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Probability (P) (X>6) = 1 - 0.9147 = 0.0853
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(b) P(X>=6) = P(X<=6.5) - P(X<=5.5) + P(X>6)
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z-score(6.5) = (6.5-6)/1.8201 = 0.2747 approximately 0.27
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P(X<=6.5) = 0.6064
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z-score(5.5) = (5.5-6)/1.8201 = -0.2747 approximately -0.27
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P(X<=5.5) = 0.3936
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P(X>=6) = 0.6064 - 0.3936 + 0.0853 = 0.2981
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(c) P(X=6) = P(X<=6.5) - P(X<=5.5) = 0.6064 - 0.3936 = 0.2128
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