A manufacturing company packages shipments in either large or small boxes. A random sample of 40 shipments that are packaged in large boxes is found to have a mean of 15 pounds and a standard deviation of 2.8 pounds. A separate random sample of 50 shipments that are packaged in small boxes is found to have a mean of 10 pounds and a standard deviation of 1.5 pounds. The manager would like to know if the data provide convincing evidence that the true mean weight of all shipments that are packaged in small boxes is less than the true mean weight of all shipments that are packaged in large boxes. Let ut = the true mean weight of all shipments that are packaged in large boxes and us = the true mean weight of all shipments that are packaged in small boxes. Are the conditions for inference met? O No, the random condition is not met.
O No, the 10% condition is not met.
O No, the Normal/large sample condition is not met:
O Yes, all of the conditions for inference have been met.​