document.write( "Question 854370: For a psychology experiment, Emma is assigned the task of finding the average number of hours U.S. college students sleep each night. Her results must be at the 99% level of confidence with a maximum margin of error of 0.1 hours. Assuming the standard deviation is 1.2 hours (based on a previous, reliable study), how many students must Emma survey? \n" ); document.write( "

Algebra.Com's Answer #514633 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( "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( "Question States***
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document.write( "ME = .1 =  2.576*1.2/sqrt(n) 
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document.write( "             n = 955.55  0r  956 rounded Up \n" );
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