A manufacturer knows that their items have a normally distributed length, with a mean of 7.3 inches, and standard deviation of 0.6 inches.

If one item is chosen at random, what is the probability that it is less than 5.5 inches long?

2 answers

Z = (score-mean)/SD

Find table in the back of your statistics text labeled something like "areas under normal distribution" to find the proportion/percentage related to the Z score.
-6.66