Concept explainers
Flawless tiles: A new process has been designed to make ceramic tiles. The goal is to have no more than 5% of the tiles be nonconforming due to surface defects. A random sample of 1000 tiles is inspected. Let
If 5% of the tiles produced are nonconforming, what is
Based on the answer to part (a), if 5% of the tiles are nonconforming, is a proportion of 0.075 nonconforming tiles in a sample of 1000 unusually large?
If the sample proportion of nonconforming tiles were 0.075, would it be plausible that the goal had been reached? Explain.
If 5% of the tiles produced are nonconforming: what is
Based on the answer to part (d), if 5% of the tiles are nonconforming, is a proportion of 0.053 nonconforming tiles in a sample of 1000 unusually large?
If the sample proportion of nonconforming tiles were 0.053, would it be plausible that the goal had been reached? Explain.
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Elementary Statistics ( 3rd International Edition ) Isbn:9781260092561
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