The Mean Replacement Time for a Random Sample of 12 $8.6$

question 110

Multiple Choice

The mean replacement time for a random sample of 12 CD players is $8.6$ years with a standard deviation of $4.4$ years. Construct the $99 \%$ confidence interval for the population variance, $\sigma ^ { 2 }$ . Assume the data are normally distributed, and round to the nearest hundredth when necessary.

• A) \(( 1.81,18.59 )\)
• B) \(( 2.82,9.04 )\)
• C) \(( 7.96,81.81 )\)
• D) \(( 8.61,69.74 )\)

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Definitions:

Sudden Infant Death Syndrome (SIDS)

The unexplained death, usually during sleep, of a seemingly healthy baby less than a year old, often related to sleep environment factors.

Emergency Department

A specialized unit in a hospital providing immediate treatment to patients with acute illnesses or injuries.

Iron Supplement

A dietary supplement used to increase the level of iron in the body, typically used to treat or prevent iron-deficiency anemia.

Simultaneously

Occurring, operating, or done at the same time.