Sample size: Nickel

A previous study of nickels showed that the standard deviationof the weight of nickels is 150 milligrams. How many nickels does a coin counter manufacturer need to weigh so that she can be 98% confident that her sample meanis with 25 milligrams of the true average weight of a nickel?

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Confidence problem
A previous study of nickels showed that the standard deviation of the weight of nickels is 150 milligrams. How many nickels does a coin counter …

The solution provides step by step method for the calculation of sample size. Formula for the calculation and Interpretations of the results are also included.