The AJAX Microchip Company produces memory chips for personal computers. The company's entire production is generated from two assembly lines, labeled I and II. Assembly line I uses more rapid assembly techniques and produces 80 percent of the company's output, while assembly line II produces 20 percent of the output. The probability that a memory chip produced on assembly line I is defective is .05 , while the corresponding probability for assembly line II is 01 .

A memory chip is chosen at random from a bin containing a day's production. Given that the chip is found to be defective, what is the probability that the chip was made on assembly line II? (Hint: Can you put this problem in a form for which Bayes rule would be applicable?)