Question

A manufacturer knows that their items have a normally distributed length, with a mean of 7.1 inches, and standard deviation of 0.7 inches.

find z score

Answer 1

This question is incomplete... Because we need X- value. In the above question has mentioned Mean and standard deviation values.

Finding Z score would be "z = (X - μ) / σ"

So with the continuation of the question , I think If one item is chosen at random, what is the probability that it is less than 6.2 inches long?

For example i kept 6.2 inches. You can refer your original value and replace with it.

z = (6.2 - 7.1) / 0.7

= -1.29

Look at -1.29 in the Z score table

0.09853 is the area of Z

9.853 is shorter than 6.2 inches