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ersity of allu exceed 5 mean H levels that the p th obtain the ercentage fall ap

ID: 3200518 • Letter: E

Question

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Explanation / Answer

= 11, = 3.5

(a) z = (x - )/ = (16 - 11)/3.5 = 1.43

(b) z1 = (10 - 11)/3.5 = -0.2857 and z2 = (15 - 11)/3.5 = 1.1429

P(10 < x < 15) = P(-0.2857 < z < 1.1429) = 0.486

(c) z = (17 - 11)/3.5 = 1.7143

P(x > 17) = P(z > 1.7143) = 0.0432