SOLUTION: A 90% confidence interval around the variance was calculated. For n=27, the confidence interval was 35.0-88.4. Give the variance of the sample.

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Question 137926: A 90% confidence interval around the variance was calculated. For n=27, the confidence interval was 35.0-88.4. Give the variance of the sample.
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
A 90% confidence interval around the variance was calculated. For n=27, the confidence interval was 35.0-88.4. Give the variance of the sample.
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(n-1)s^2/(Ch-Sq right) = 35
26*s^2/41.923 = 35
s^2 = 35*41.923/26
s^2 = 56.434
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(n-1)s^2/(Ch-Sq left) = 88.4
26*s^2/15.379 = 88.4
s^2 = 88.4*15.379/26
s^2 = 52.2886
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The discrepancy is probably due to my Ch-Sq table truncating its values.
It gives the Ch-Sq. left and right values as indicated. Your chart
may give values with greater decimal precision.
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Cheers,
Stan H.