Assume that the random variable X has normal distribution. The mean is ? = 80 and the standard deviation is ? = 10. Find the probability that X < 70 (P (X < 70)) A) 0.841 B) 0.5589 C) 0.0228 D) 0.159
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Z = (70 - 80) / 10 Z = -1 Show more…
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