Complete question is;
Assume the random variable X is normally distributed with mean μ = 50 and standard deviation σ = 7. What is the probability P (X > 42)?
Answer:
P(X > 42) = 0.1271
Step-by-step explanation:
We are given;
mean; μ = 50
Standard deviation; σ = 7
Formula for the z-score is;
z = (x - μ)/σ
Thus;
z = (42 - 50)/7
z = -1.14
Since we are looking for P (X > 42), then let's look up this z-value from the z-distribution table attached.
We have;
P(X > 42) = 0.1271