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Suppose a variable x is normally distributed with a standard deviation of 10. given that 30.85% of the values of x are greater than 70, what is the mean of x?

User Megaoctane
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The 69.15 percentile corresponds to 0.500 standard deviations above the mean. If 70 is 10*.500 = 5 units above the mean, then the mean is 65.
User Thomas Chilinski
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