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In: Statistics and Probability

As part of a water quality​ survey, you test the water hardness in several randomly selected...

As part of a water quality​ survey, you test the water hardness in several randomly selected streams. The results are shown below. Construct a confidence interval for the population variance sigma squared and the population standard deviation sigma. Use a 99 % level of confidence. Assume that the population has a normal distribution.
nequals24
sequals16 grains per gallon

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Expert Solution

Refer chi-square table or use excel formula "=CHISQ.INV.RT(0.995,23)" & "=CHISQ.INV.RT(0.005,23)" to find the critical values.

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orchestra answered 2 years ago
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