X is a normally distributed random variable with μx = 125 and σx = 12.5.What is P(X ≥ 110)?
A) 0.1151
B) 0.3849
C) 0.8849
D) 0.6151

Question

Quizplus · Accepted Answer

To find P(X ≥ 110) for a normally distributed variable, we use the Z-score formula: Z = (X - μ) / σ. Here, Z = (110 - 125) / 12.5 = -1.2. Looking up the Z-score in a standard normal distribution table or using a calculator, we find the probability to the left of Z = -1.2. This is approximately 0.1151. Since we want P(X ≥ 110), we subtract this from 1 to get 1 - 0.1151 = 0.8849.

X Is a Normally Distributed Random Variable with μX =