#2

A manufacturing company uses an acceptance scheme on production items before they are shipped. The plan consists of two stages, that is, boxes of 25 are readied for shipment and a sample of 3 are tested for defectives. If no defectives are found the box is shipped.

What is the probability that

a) a box containing 3 defectives will be shipped?

b) a box containing only 1 defective will be sent back for screening?

Thank you very very much in advance!