In a Manufacturing Process a Random Sample of 9 Bolts

question 107

Multiple Choice

In a manufacturing process a random sample of 9 bolts manufactured has a mean length of 3 inches with a standard deviation of .3 inches.What is the 95% confidence interval for the true mean length of the bolt?

• A)2.804 to 3.196
• B)2.308 to 3.692
• C)2.770 to 3.231
• D)2.412 to 3.588
• E)2.814 to 3.186

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Definitions:

Confidence Interval Estimate

A range of values, derived from sample data, that is likely to contain the value of an unknown population parameter, with a specified level of confidence.

Population Variance

The average of the squared differences from the Mean, representing the variance of an entire population.

Chi-Square Value

A statistic that measures the discrepancy between observed and expected frequencies in categorical data, used in hypothesis testing.

Confidence Interval

A range of values, derived from sample statistics, that is likely to contain the value of an unknown population parameter with a specified level of confidence.