document.write( "Question 1173026: Construct the confidence interval for the population mean u.
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Algebra.Com's Answer #798181 by ewatrrr(24785)\"\" \"About 
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document.write( "Hi, ME =\"+z%2Asigma%2Fsqrt%28n%29\"
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document.write( "c=.98, X= 15.1 , o=9.0 ​, and n= 85
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document.write( "From table: DF = 85-1 = 84,  , z = 2.3716
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document.write( "DF    0.1     0.05    0.02    0.01 
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document.write( "83  1.6634  1.9889  2.3721  2.6364   
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document.write( "84  1.6632  1.9886  \"highlight_green%282.3716%29\"     
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document.write( "85  1.6630  1.9883  2.3710  2.6349   
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document.write( "ME =\"+2.3716%289%29%2Fsqrt%2885%29\"= 2.31
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document.write( "CI: 15.1-2.31 < u < 15.1+2.31
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document.write( "CI: 12.79 < u < 17.41
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document.write( "Note:  we used the smaller sample size z = 2.37
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document.write( "NEED to Know:  
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document.write( "What is considered a Large Enough Sample Size  to use z scores below 
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document.write( "	a	a/2	2-tailed crtical regions	
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document.write( "80%	0.2	10%z <-1.28155	z >+1.28155
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document.write( "90%	0.1	5%	z <-1.645	z >+1.645
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document.write( "92%	0.08	4%	z <-1.751	z >+1.751
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document.write( "95%	0.05	2.50%	z <-1.96	z >+1.96
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document.write( "98%	0.02	1%	z <-2.326	z >+2.326
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document.write( "99%	0.01	0.50%	z<-2.576	z >+2.576
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