A Lumber Mill Is Tested for Consistency by Measuring the Variance

question 113

Multiple Choice

A lumber mill is tested for consistency by measuring the variance of board thickness. The target accuracy is a variance of $0.0035$ square inches or less. If 28 measurements are made and their variance is $0.006$ square inches, is there enough evidence to reject the claim that the standard deviation is within the limit at $\alpha = 0.01$ ?

• A) Yes, since the \(\chi ^ { 2 }\) test value \(8.91\) is less than the critical value 48.278.
• B) Yes, since the \(\chi ^ { 2 }\) test value \(8.91\) is less than the critical value 46.963.
• C) No, since the \(\chi ^ { 2 }\) test value \(46.29\) is less than the critical value \(46.963\).
• D) No, since the \(\chi ^ { 2 }\) test value \(46.29\) is less than the critical value \(48.278\).

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