document.write( "Question 1148746: A college has 25000 students. Based on student personal information data, approximately 45 percent are Democrats. A simple random sample of 900 households were selected for a survey. The percentage of Democrats in the sample will be around ___ give or take ____ or so.\r
\n" ); document.write( "\n" ); document.write( "Estimate the chance that between 42.45 percent and 47.55 percent of the students in the sample are Democrats. ___
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Algebra.Com's Answer #770249 by Boreal(15235)\"\" \"About 
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give or take means margin of error is 1/sqrt(n) or 1/30 or 0.033 or 3.3%
\n" ); document.write( "so it would be around 42-48 %\r
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\n" ); document.write( "\n" ); document.write( "This is not exact (that would be between 41.75 and 48.25%)\r
\n" ); document.write( "\n" ); document.write( "For the estimate
\n" ); document.write( "half-interval is z* sqrt(0.45*0.55/900)=0.0255
\n" ); document.write( "z^2*0.45*0.55/900=0.0255^2
\n" ); document.write( "z^2=2.36
\n" ); document.write( "z=+/-1.54
\n" ); document.write( "This would encompass 88% of the probability.\r
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