You can put this solution on YOUR website! N=75, find the probability of a sample mean being greater than 229 if mean =228 and standard deviation = 6.1
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z(229) = (229-228)/(6.1/sqrt(75)) = sqrt(75)/6.1 = 1.4197
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p(x-bar > 229) = P(z > 1.4197) = normalcdf(1.4197,100) = 0.0778
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Cheers,
Stan H.
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