Assume that the random variable X is normally distributed, with mean μ = 60 and standard deviation σ = 16.Compute the probability P(X

Question

Assume that the random variable X is normally distributed, with mean μ = 60 and standard deviation σ = 16.Compute the probability P(X < 80).
A) 0.8944
B) 0.8849
C) 0.1056
D) 0.9015

Quizplus · Accepted Answer

To find P(X < 80) for a normally distributed variable X with mean μ = 60 and standard deviation σ = 16, we use the Z-score formula: Z = (X - μ) / σ. Substituting the given values, we get Z = (80 - 60) / 16 = 20 / 16 = 1.25. Looking up the Z-score of 1.25 in a standard normal distribution table or using a calculator, we find the probability is approximately 0.8944.

Assume That the Random Variable X Is Normally Distributed, with Mean