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
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.