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In: Statistics and Probability

You want to estimate the mean amount of time internet users spend on Facebook each month....

You want to estimate the mean amount of time internet users spend on Facebook each month. How many internet users must be surveyed to be 90% confident that your sample mean is within 10 minutes of the population mean? Use 210 minutes as an estimate of the population standard deviation.

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Expert Solution

We have given here,                  
                  
Population standard deviation =   210  
Margin of error =E=10  
Level of significance =1-0.90=0.1  
Z critical value is (by using Z table)=1.645  
Sample size formula is                   


=1193.36

orchestra answered 2 years ago
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