Question

A component is rejected if its has a diameter less than 70mm, reworked if the diameter is between 70 and 73.5mm or more than 78.5mm. The diameter of a component is normally distributed with a mean 76mm and standard deviation 2.5mm. In a batch of 400 components, determine the number of components:
(1) that are rejected,
(2) that are accepted

Answer 1

Z = (score-mean)/SD

Find table in the back of your statistics text labeled something like "areas under normal distribution" to find the proportion/probability related to the Z scores. Multiply by 400.

Answer 2

For above question