40. In a factory 4000 units of an item are produced. There are three machines A, B and C in the factory. B and C produce equal number of items while machine A produces double items than B. The proportion of defective items produced by A, B and C are 2%, 1% and 3% respectively. An item is selected at random from the total production and it is found to be defective. Find the probability that it comes from machine C.

[Ans. : 3/8]