Find the indicated probability.
-The incomes of trainees at a local mill are normally distributed with a mean of $1100 and a standard deviation of $150. What percentage of trainees earn less than $900 a month?
A) 40.82%
B) 35.31%
C) 9.18%
D) 90.82%

Question

Quizplus · Accepted Answer

To find the probability that a trainee earns less than $900 a month, we need to find the z-score for $900 using the formula:

z = (x - μ) / σ = (900 - 1100) / 150 = -1.33

Using a standard normal distribution table, we can find that the probability of a z-score less than -1.33 is 0.0918, or 9.18%. Therefore, choice C is the best answer.

Find the Indicated Probability