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)9.18%
B)40.82%
C)35.31%
D)90.82%

Question

Quizplus · Accepted Answer

To find the percentage of trainees earning less than $900, we calculate the z-score: $z = \frac{X - \mu}{\sigma} = \frac{900 - 1100}{150} = -\frac{200}{150} = -1.33$. Looking up -1.33 on the standard normal distribution table gives us approximately 9.18%.

The Incomes of Trainees at a Local Mill Are Normally