question_answer 1)

An electronic assembly consists of two systems, say, A and B. From previous testing procedure, the following probabilities are assumed to be known : P(A fails) = 0.2, P(B fails alone) = 0.15 and P(A and B fail) = 0.15. Evaluate (i) P (A fails/B has failed) (ii) P(A fails alone)  

Answer:

Let E and F are the events respectively A fails and B fails.       We have, P(E) = 0.2, P() = 0.15 and                   (i) Required probability             (ii) Required probability