Question

In: Statistics and Probability

Twenty-five wooden beams were ordered for a construction project. The sample mean and the sample standard...

Twenty-five wooden beams were ordered for a construction project. The sample mean and the sample standard deviation were measured: x¯=180 cm, s=1 cm⁢. Calculated confidence interval for the mean is [179.59;180.41].


Which confidence level was chosen? Assume distribution to be normal.

Solutions

Expert Solution

95 % Confidence Level chosen.

180   2.06 ( 1/ 25 )

180   0.413

( 179.59 , 180.41 )

At 95 % , CI for Mean is ( 179.59 , 180.41 )


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