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Statistics - Population Variance - Confidence Interval

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The grades of a sample of 5 students, selected from a large population, are given below.
Grade
70
80
60
90
75
a. Determine a point estimate for the variance of the population.
b. Determine a 95% confidence interval for the variance of the population.
c. At 90% confidence, test to determine if the variance of the population is significantly more than 50.

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Solution Summary

The expert examines the confidence intervals for a population variance. A complete, neat and step-by-step solution is provided in the attached file.

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