Question

In: Statistics and Probability

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.

Solutions

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  


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