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The time to failure of 10 batteries was measured. The average time to failure of the...

The time to failure of 10 batteries was measured. The average time to failure of the 10 batteries is 12.62 hours and the standard deviation of the 10 batteries is 0.96 hours. The population is assumed to be normally distributed.

Determine a 95% confidence interval for sigma

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Answer #1

Let X be the time to failure of batteries.

Given, n=10

s=0.96

The 95% confidence interval for population standard deviation is



The 95% confidence interval for sigma is

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