Math/Probability

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The random variable X has a log-normal distribution, when the mean of ln(X) = 5.45 and variance of ln(X) = 0.334,

what is the probability that X >139.76?

  • Math/Probability -

    ln(139.76) = 4.94

    So, just look up Z>(4.94-5.45)/0.334

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