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Confidence Interval & Sample standard deviation

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A 90% confidence interval runs from 65.891 to 70.109 for the mean daily number of credit card applications that are rejected from a computer system and must be handled manually. The confidence interval was obtained from a sample of 45 randomly selected days that had a sample mean of 68. What is the sample standard deviation?

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Solution Summary

The sample standard deviation is calculated when the problem provides data on 90% confidence interval and sample mean.

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A 90% confidence interval runs from 65.891 to 70.109 for the mean daily number of credit card applications that are rejected from a computer system and must be handled manually.  The ...

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