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

question 120

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) \(108.6 < \sigma ^ { 2 } < 269.6\)
• B) \(10.4 < \sigma ^ { 2 } < 16.4\)
• C) \(123.7 < \sigma ^ { 2 } < 312.7\)
• D) \(122.8 < \sigma ^ { 2 } < 316.5\)

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Definitions:

Sensory Information

Information received through the senses (sight, hearing, touch, taste, and smell), which is then processed by the brain to understand and interact with the environment.

Past Memory

Recollections and information from previous experiences stored in the brain.

Perception

The process by which individuals organize and interpret their sensory impressions to give meaning to their environment.

Sensation

The process by which sensory receptors and nervous system receive and represent stimulus energies from our environment.