The Mean of the Sample Means and the Pooled Standard $\bar { x }$

question 65

Multiple Choice

The mean of the sample means and the pooled standard deviation of 40 samples of size 5 taken from a production process under control are found to be 400 and 15,respectively.The lower control limit for the $\bar { x }$ chart is:

• A) 460.37
• B) 392.88
• C) 379.88
• D) None of these choices.

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Definitions:

Aromatic

Refers to compounds that contain a ring of continuously overlapping p-orbitals, displaying enhanced stability as seen in benzene.

Nonaromatic

Refers to organic compounds that do not fulfill the criteria for aromaticity, lacking a conjugated system of pi electrons.

Phenanthrene

A polycyclic aromatic hydrocarbon made up of three fused benzene rings, found in coal tar and crude oil.

Carbon Tetrachloride

A colorless liquid with the formula CCl4, historically used as a cleaning agent, fire extinguisher, and refrigerant, now recognized as a carcinogen.