Question:
An electronic assembly consists of two subsystems, say, A and B. From previous testing procedures, the following probabilities are assumed to be known: $P(\text{A fails}) = 0.2$, $P(\text{B fails alone}) = 0.15$, $P(\text{A and B fail}) = 0.15$. Evaluate the following probabilities (i) $P(\text{A fails}|\text{B has failed})$ (ii) $P(\text{A fails alone})$.