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Confidence Interval: Breaking Strengths of Cables

The breaking strengths of cables produced by a certain manufacturer have a standard deviation of 82 pounds. A random sample of 150 newly manufactured cables has a mean breaking strength of 1950 pounds. Based on this sample, find a 95% confidence interval for the true mean breaking strength of all cables produced by this manufacturer. Then complete the table below.

Carry your intermediate computations to at least three decimal places. Round your answers to one decimal place.

What is the lower limit of the 95% confidence interval?
What is the upper lint of the 95% confidence interval?

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Statistics, All Topics
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The breaking strengths of cables ...

Solution Summary

In this solution, the 95 % confidence interval for the breaking strengths of cables is determined. The lower confidence limit and upper confidence limit are calculated for the data. The solution is enclosed within an attached Word document.