Question

In: Statistics and Probability

If X is a normal random variable with mean ( μ ) = 50 and standard...

If X is a normal random variable with mean ( μ ) = 50 and standard deviation ( σ ) = 40, then the probability of X > 80 is: a. 0.0000 b. 0.7734 c. 1.0000 d. 0.2266

Solutions

Expert Solution

µ = 50

sd = 40

                        

                         = P(Z > 0.75)

                         = 1 - P(Z < 0.75)

                         = 1 - 0.7734

                         = 0.2266

Option-D) 0.2266


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