Example 1: A farmer knows his average sale is 3.5 pounds of vegetables with a standard deviation of 1 pound. If the standard error is 0.11 , what is the confidence interval for this mean? [ egin{array}{rllll} ext { Estimate +/- } & ext { (Reliability Factor) } & ext { (Standard Error) } & = ext { Confidence Interval } \ 3.5 & ext { +/- } & ext { (1.96) } & ext { (0.11) } & =3.5+/-0.22 ext { or } 3.3 ext { and } 3.7 end{array} ] We can be ( 95 % ) confident the mean lies between 3.3 and 3.7 .
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The problem provides the average sale of vegetables as 3.5 pounds with a standard deviation of 1 pound. The standard error of the mean (SEM) is given as 0.11. We are asked to find the confidence interval for the mean. Show more…
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