Question

A glue company needs to make some glue that it can sell at $120 per barrel. It wants to use 150 barrels of glue worth $100 per barrel, along with some

Confidence intervals
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asked 2021-06-14

Assume the sample is from a normally distributed population and construct the indicated confidence intervals for (a) the population variance \(\displaystyleσ^{{{2}}}\) and (b) the population standard deviation σ. Interpret the results. The reserve capacities (in hours) of 18 randomly selected automotive batteries have a sample standard deviation of 0.25 hour. Use an 80% level of confidence.

Expert Answers (1)

2021-06-15
Variance: (0.0426,0.1054)
Standard deviation: (0.2071, 0.3246)
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