A factory received a shipment of 10 compressors, and the vendor who sold the items knows there are 4 compressors in the shipment that are defective. Before the receiving foreman accepts the delivery,...

A factory received a shipment of 10 compressors, and the vendor who sold the items knows there are 4 compressors in the shipment that are defective. Before the receiving foreman accepts the delivery, he samples the shipment, and if too many of the compressors in the sample are defective, he will refuse the shipment. Give answer as a decimal to three decimal places.


(a) If a sample of 4 compressors is selected, find the probability that all in the sample are defective.





(b) If a sample of 4 compressors is selected, find the probability that none in the sample are defective.