document.write( "Question 885317: Random sample of size 100 has a standard deviation of 5.What can be said about maximum error with 95% confidence? \n" ); document.write( "

Algebra.Com's Answer #535060 by Theo(13342) $\"\"$ $\"About$

You can put this solution on YOUR website!
sample size = 100
\n" ); document.write( "standard deviation = 5.
\n" ); document.write( "standard error = standard deviation divided by square root of sample size.
\n" ); document.write( "standard error = 5/sqrt(100) = 5/10 = .5
\n" ); document.write( "two sided alpha for two sided confidence limit of 95% is calculated below:
\n" ); document.write( "two sided alpha = (100% - 95%) / 200 = 5% / 200 = .025
\n" ); document.write( "critical z factor for two sided alpha of .025 is calculated below:
\n" ); document.write( "critical z factor = z factor for (1 - .025) = z factor for .975 = 1.96
\n" ); document.write( "margin of error = critical z factor * standard error = 1.96 * .5 = .98
\n" ); document.write( "confidence interval = mean plus or minus margin of error = mean plus or minus .98
\n" ); document.write( "since you don't have a mean, you can't calculate the confidence interval.
\n" ); document.write( "your maximum error with 95% confidence level is equal to plus or minus .98 from the mean.\r
\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "

\n" );