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Confidence Interval

A journal article reports that a sample of size 5 was used as a basis for calculating a 95% confidence interval for the true average natural frequency (Hz) of delaminated beams of a certain type. The resulting interval was [216.3, 217.8]
You decide that a confidence level of 99% is more appropriate than the 95% level used. Hint: Use the center of the interval and its width to determine the mean and standard error.

a) What is the lower limits of the 99% interval? Give your answers to three decimal places.

b) What is the upper limit of the 99% interval? Give your answers to three decimal places

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A journal article reports that a sample of size 5 was used as a basis for calculating a 95% confidence interval for the true average natural frequency (Hz) of delaminated beams of a certain type. The resulting interval was [216.3, 217.8] . You decide that a confidence level of 99% is more appropriate than the 95% level used. Hint: Use the center of the interval and its width to determine the mean and standard error.

What is the lower limits of the 99% interval? Give your ...

Solution Summary

Calculates the confidence interval

$2.19