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In: Statistics and Probability

An engineer randomly inspected 140 rural bridges in a state and found that 50 had serious...

An engineer randomly inspected 140 rural bridges in a state and found that 50 had serious problems. What is a 95% confidence interval for the proportion of bridges in the state with serious problems? (Show work)

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Expert Solution

We have given here,                              
                              
x=50                          
n=140                          
Estimate for sample proportion                              

Level of significance is =1-0.95=0.05                      
Z critical value(using Z table)=1.96                      

orchestra answered 2 years ago
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