Question
In a factory which manufactures bolts, machines A, B and C manufacture respectively 25%, 35% and 40% of the bolts. Of their outputs, 5, 4 and 2 percent are respectively defective bolts. A bolt is drawn at random from the product and is found to be defective. What is the probability that it is manufactured by the machine B?
Solution
Let E1 , E2, E3 be the events that the bolt is produced by machines A, B, C respectively.
Let D be the event of the bolt being defective.
Let D be the event of the bolt being defective.
