A factory produces a certain type of output by three types of machines. The

respective daily production figures are Machine I: 3,000 units, Machine II: 2,500 units and Machine III: 4,500 units. = 800

Past experience shows that 1% of the output produced by Machine I is defective. The corresponding fraction of defectives for the other two machines are 1.2% and 2% respectively. An item is drawn at random from the day's production run and is found to be defective. What is the probability that it comes from the output of (a) Machine 1, (b) Machine II and (c) Machine III?