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Takalm
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Takalm
Hi Guys

I need some help with a question below:
Three workers produce a certain part at the same rate .Joe averages 2 defective parts per hundred.Mary averages 5 defective parts per hundred.Harold averages 8 defective parts per hundred.The defective parts are identified by quality control and set aside in a rework pile.

How many defective parts do you expect there to be out of 1000 parts produced?

What is the probability that a randomly selected part in the rework pile was produced by Mary?

If they each produced 100 (for 300 total), how many defective parts are there?
Answer: 2+5+8 = 15.

Mary produced 5 of these 15.
So, if we randomly selected a part in this rework pile, the probability of it being Mary's is 5/15 = 1/3 = 33%

For every 300 parts produced, 15 are defective, as we figured out above.
So for every 100 parts produced, 5 are defective. (divided both sides by 3)

Then, for every 1000 parts produced, 50 are defective. (multiply both by 10).
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