What Is the 90% Confidence Interval for the Variance of Exam

question 21

Multiple Choice

What is the 90% confidence interval for the variance of exam scores for 28 algebra students, if the standard deviation of their last exam was 12.7?

• A) \(1086 < \sigma ^ { 2 } < 269.6\)
• B) \(10.4 < \sigma ^ { 2 } < 164\)
• C) \(1237 < \sigma ^ { 2 } < 312.7\)
• D) \(122.8 < \sigma ^ { 2 } < 316.5\)

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AutoShift Transmission

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Inertia Brake

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A group of batteries connected together in a vehicle to supply electrical power, especially in electric and hybrid vehicles.