SOLUTION: 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 manufacturer need to weigh so that
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Question 287251: 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 manufacturer need to weigh so that she can be 98% confident that her sample mean is within 25 milligrams of the true average weight of a nickel Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website! 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 manufacturer need to weigh so that she can be 98% confident that her sample mean is within 25 milligrams of the true average weight of a nickel
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n = [zs/E]^2
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n = [2.3263*150/25]^2
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n = 194.82
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Round up to 195
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Cheers,
Stan H.
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