document.write( "Question 852820: find the sample size necessary to estimate the mean weight of all supermodels so that there is 95% confidence that the sample mean is in error by no more than 2 lb. assume that a pilot study suggests that the weights of all supermodels have a std dev of 7.5 lbs\r
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Algebra.Com's Answer #513789 by ewatrrr(24785) $\"\"$ $\"About$

You can put this solution on YOUR website!

 
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document.write( "Hi,
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document.write( " = C	z = 1.28155
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document.write( "90%	z =1.645
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document.write( "92%	z = 1.751
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document.write( "95%	z = 1.96
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document.write( "98%	z = 2.326
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document.write( "99%	z = 2.576
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document.write( "ME = 1.96*7.5/sqrt(n) < 2,  n = 54.0225   0r   55 rounded Up
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document.write( "sample size necessary is 55\r
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