|
Question 1099480: Weekly wages at a certain factory are normally distributed with a mean of $400 and a standard deviation of $50. Find the probability that a worker selected at random makes between $300 and $350.
Answer by htmentor(1343) (Show Source):
You can put this solution on YOUR website! We first calculate the z-scores, and then use z-score tables, calculator, etc. to compute the probability.
Let z = (x-mu)/sigma where mu = the mean and sigma = the standard deviation
Our two z values therefore are z = (300-400)/50 = -2 and z = (350-400)/50 = -1
From tables, P(z <= -2) = 0.02275 and P(z <= -1) = 0.15866
Thus P(-2 <= z <= -1) = 0.15866 - 0.02275 = 0.1359
|
|
|
| |