Question

In a factory, Machine-I produces 45% of the output and Machine-II produces 55% of the output. On the average 10% items produced by I and 5% of the items produced by II are defective. An item is drawn at random from a day’s output, 

(i) Find the probability that it is a defective item 

(ii) If it is defective, what is the probability that it was produced by Machine-II?

Answer 1

Let A₁ and A₂ be the events that the items produced by Machine-I and II respectively.

Let B be the event of selecting a defective item

(i) P(B) 

(ii) P(A₂/B)