Confidence interval for average length of long distance call

Reference no: EM131372568

A telephone company wants to estimate the average length of long-distance calls during weekends. A random sample of 50 calls gives a mean x‾ = 14.5 minutes and standard deviation s = 5.6 minutes.

Give a 95% confidence interval and a 90% confidence interval for the average length of a long-distance phone call during weekends.

Reference no: EM131372568

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