Math

X is a normal variable with mean 9. If P(X > 12) = 0.0062, calculate the standard deviation, the standard deviation if X.

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  1. (12-9)/sd = 2.5

    I got 2.5 by finding the inv of .0062

    3/sd = 2.5

    3/2.5 = sd sd = 1.2

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