Answer :
Answer: Our required probability is 6.3%.
Step-by-step explanation:
Since we have given that
Probability that worker operated machine produces a defective item if follow the instruction exactly = 0.06
Probability that worker produces defective item if he does not follows the machine's operating instructions exactly = 0.09
Probability that the worker follows the instruction = 90% = 0.9
Let A be the event that worker follow the instructions.
Let B be the event that machine produce defective items.
So, P(A) = 0.9, P(A') = 0.1
P(B|A) = 0.06 , P(B|A') = 0.09
So, Probability that all items produced by the machine will be defective is given by
[tex]P(A).P(B|A)+P(A')P(B|A')\\\\=0.9\times 0.06+0.1\times 0.09\\\\=0.063\\\\=6.3\%[/tex]
Hence, our required probability is 6.3%.