Schadek Silkscreen Printing Inc. purchases plastic cups on which to print logos for sporting events, proms, birthdays, and other special occasions. Zack Schadek, the owner, received a large shipment this morning. To ensure the quality of the shipment, he selected a random sample of 300 cups. He found 15 to be defective.
(a) What is the estimated proportion defective in the population? (Round your answer to 2 decimal places.)
(b) What are the endpoints of a 95 percent confidence interval for the proportion defective. (Round your answers to 3 decimal places.)
(c) Zack has an agreement with his supplier that he is to return lots that are 10 percent or more defective. Should he return this lot?
( )- no, lot not 10% defective
( )- yes, the lot is 10% defective
( )- yes 15 is outside the confidence interval