A factory has three machinesX,YandZproducing 1000, 2000 and 3000 bolts per day respectively. The machineXproduces 1% defective bolts,Yproduces 1.5% andZproduces 2% defective bolts. At the end of a day, a bolt is drawn at random and is found to be defective. What is the probability that this defective bolt has been produced by machineX?
