Seiko purchases watch stems for their watches in lots of 10,000. Seiko's sampling plan calls for checking 20 stems, and if 3 or fewer stems are defective, the lot is accepted.
a. Based on their sampling plan, what is the probability that a lot of 40 percent defective will be accepted?
b. Design an OC curve for incoming lots that have zero, 10 percent, 20 percent, 30 percent, and 40 percent defective stems.