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?
(1 point)
Responses
9.18%
40.82%
90.82%
35.31%
To find the percentage of trainees who earn less than $900 a month, we need to standardize the value using the z-score formula:
z = (X - μ)/σ
where X is the income ($900), μ is the mean ($1100), and σ is the standard deviation ($150).
z = (900 - 1100) / 150
z = -200 / 150
z = -1.33
Using a z-score table or calculator, we can find that the percentage of trainees earning less than $900 a month is approximately 9.18%.
Therefore, the answer is:
9.18%