# Question about Hypothesis test regarding a standard deviation

The standard deviation of the breaking strengths of certain cables produced by a company is given as 240 pounds. After a change was introduced in the process of manufacture of these cables, the breaking strengths of a sample of 8 cables showed a standard deviation of 300 pounds. Investigate the significance of the apparent increase in variability, using a significance level of (a) 0.05 (b) 0.01.

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#### Solution Summary

This problem is a test of hypothesis comparing the variance ( and standard deviation) of a new distribution with a known variance from another distribution. A step-by-step process is used, all formulas and calculations are shown and each step is explained.

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