# calculating the probability that an item is defective.

Question was asked previously and the calculations not detailed enough for me to determine how the answer was received. Please provide detailed explanation - I got a different answer and I KNOW mine is not right!

Question: A manufacturing process produces units that average 10 inches in length with a standard deviation of 3.2 inches. If only those units between 9.5 and 10.5 inches can be used, how many out of sample of 100 must be thrown away?

THANK YOU!!!

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#### Solution Preview

In order to answer this question, you must determine the z score for units with measurements of 9.5 and 10.5. Thus

z = (x - mean)/standard deviation

z for 9.5 = (9.5 - 10) / 3.2 = ...

#### Solution Summary

The following exercise uses a z-score to calculate the number of items from a manufacturing process that will need to be thrown out due to defectiveness.