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In: Statistics and Probability

A research scientist wants to know how many times per hour a certain strand of bacteria...

A research scientist wants to know how many times per hour a certain strand of bacteria reproduces. The mean is found to be 13.6 reproductions and the population standard deviation is known to be 1.9 . If a sample of 189 was used for the study, construct the 85 % confidence interval for the true mean number of reproductions per hour for the bacteria. Round your answers to one decimal place.

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Expert Solution

We have given that,                              
                              
Sample mean =   13.6                      
Population standard deviation=   1.9                  
Sample size=189                      
Level of significance =1-0.85=0.15                      
Z critical value (by using Z table)=1.44                  
                              
Confidence interval formula is


=(13.4,13.8)                              
                              

orchestra answered 2 years ago
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