Hypergeometric Probability Formula P ( X = k ) = ( D k ) ( N D n k ) ( N n )

RDB Co. orders 500 lathe machines from Supplier A. To check whether to accept the supplied machines, the manager of RDB Co. tests 12 lathe machines before the delivery date. If none of the 12 randomly selected machines is found to be defective, the manager will consider the shipment acceptable. What is the probability that none of the selected machines are defective if 10% of the batch of lathe machines are defective