Schadek Silkscreen Printing, Inc., buys plastic cups on which to print logos for sporting events, proms, birthdays, and other special occasions. Zack Schadek, owner, received the large shipment this morning. To make sure the quality of shipment, he selected the random sample of 300 cups. He found 15 to be defective.
- Determine the estimated proportion defective in population?
- Make a 95 percent confidence interval for proportion defective.
- Zack has the agreement with his supplier that he is to return lots that are 10 percent or more defective. Should he return this lot? Describe your decision.