SOLUTION: A production process produces an item. On average 20% of all items produced are defective. Each item is inspected before being shipped. The inspector misclassifies an item 10% of t

Algebra.Com
Question 1206541: A production process produces an item. On average 20% of all items produced are defective. Each item is inspected before being shipped. The inspector misclassifies an item 10% of the time, i.e. probability (classified/defective item) = Probability (classified defective/good item).
a. What proportions of the items will be classified defective.
b. Suppose that only items classified as good after inspection are shipped;
(i). What percentage of the items shipped are good.
(ii). What percentage of those shipped are good.

Answer by Theo(13342)   (Show Source): You can put this solution on YOUR website!
to be reviewed and re-posted when more time is available.
stay tuned.

80% of the total are actually good.
20% of the total are actually defective.

10% of the good are mis-classified as defective.
10% * 80% = 8% that are mis-classified as defective.
that leaves 80% minus 8% = 72% that are correctly classified as good.

10% of the defective are mis-classified as good.
10% * 20% = 2% that are mis-classified as good.
that leaves 20% minus 2% = 18% that are correctly classified as defective.

you have 72% that are correctly classified as good and 2% that are incorrectly classified as good for a total of 74% classified as good.

you have 18% that are correctly classified as defective and 8% that are incorrectly classified as defective for a total of 26% classified as defective.

totals look good.

80% actually good plus 20% actually defective = 100% total.
74% classified good plus 26% classified defective = 100% total.

this agrees with my original assessment.
let me know if you have any questions or concerns.
theo



RELATED QUESTIONS

A production process produces an item. On average, 15% of all items produced are... (answered by stanbon)
A production process produces an item. On average, 15% of all items produced are... (answered by Edwin McCravy,math_tutor2020)
A production process produces an item. On average, 10% of all items produced are... (answered by Boreal)
Seven percent of the items produced at a factory are defective. The quality control team... (answered by robertb)
As items come to the end of a production line, an inspector chooses which items are to go (answered by edjones)
Machine A produces 3% defectives, machine B produces 5% defectives, and machine C... (answered by ewatrrr)
A machine used in a production process is set up correctly 97% of the time. Given that... (answered by Theo)
On average, 17% of all items produced are defective. The inspector misclassifies an item (answered by edjones)
Can someone help me with this problem: In a certain production process, 25% of the... (answered by rothauserc,ewatrrr)