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Confidence Intervals

To estimate the mean size of maple trees in a certain area of the Adirondacks. A sample of 15 maple tree heights is collected (refer to the data set).

Data Sheet numbers:
50, 41, 31, 33, 47, 39, 41, 44, 39, 32, 35, 43, 37, 49, 51

a) Determine a 90% confidence interval for the population mean of maple tree heights.

b) Determine a 99% confidence interval for the population mean of maple tree heights.

c) What size sample would you need to estimate the average heights of the trees to within ft. with a 99% confidence (assume o=s from your data set)

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To estimate the mean size of maple trees in a certain area of the Adirondacks. A sample of 15 maple tree heights is collected (refer to the data set).

Data Sheet numbers:
50, 41, 31, 33, 47, 39, 41, 44, 39, 32, 35, 43, 37, 49, 51

a) Determine a 90% confidence interval for the population mean of maple tree heights.
Column1

Mean 40.8
Standard Error 1.688053
Median 41
Mode 41
Standard Deviation 6.537802
Sample ...

Solution Summary

To estimate the mean size of maple trees in a certain area of the Adirondacks. A sample of 15 maple tree heights is collected (refer to the data set).

Data Sheet numbers:
50, 41, 31, 33, 47, 39, 41, 44, 39, 32, 35, 43, 37, 49, 51

a) Determine a 90% confidence interval for the population mean of maple tree heights.

b) Determine a 99% confidence interval for the population mean of maple tree heights.

c) What size sample would you need to estimate the average heights of the trees to within ft. with a 99% confidence (assume o=s from your data set)

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