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

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Expert Solution

µ = 50

sd = 40

= P(Z > 0.75)

= 1 - P(Z < 0.75)

= 1 - 0.7734

= 0.2266

Option-D) 0.2266

orchestra answered 1 year ago

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