6. A random sample of 18 students obtained a mean score of 82 and a variance...
6. A random sample of 18 students obtained a mean score of 82 and a variance of s2=16 on a college placement test in science. Assuming the scores to be normally distributed, construct a 90 percent confidence interval for variance, σ2.
Homework Answers
Solution:
The 90% confidence interval for the variance is:
Where:
Therefore, we have:
Therefore, the 90% confidence interval for variance is (9.860,31.365)
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