Noise levels at 6 volcanoes were measured in decibels yielding the following data: 135,137,146,138,123,133 Construct the...

Noise levels at 6 volcanoes were measured in decibels yielding the following data: 135,137,146,138,123,133 Construct the 80% confidence interval for the mean noise level at such locations. Assume the population is approximately normal. Copy Data Step 4 of 4 : Construct the 80% confidence interval. Round your answer to one decimal place.

Expert Solution

We have given that,

Sample mean =135.3333
Sample standard deviation =7.5011
Sample size =6
Level of significance=   1-0.80=0.2
Degree of freedom =5

t critical value is (by using t table)=   1.476

Confidence interval formula is

=(130.8,139.9)



Lower confidence limit=130.8

Upper confidence limit=139.9

orchestra answered 3 years ago

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