document.write( "Question 1204517: Construct the indicated confidence interval for the population mean μ using the​ t-distribution. Assume the population is normally distributed.
\n" ); document.write( "c=0.90​, x=13.5​, s=0.77​, n=15
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Algebra.Com's Answer #840832 by MathLover1(20850)\"\" \"About 
You can put this solution on YOUR website!

\n" ); document.write( "The formula for estimation is:\r
\n" ); document.write( "\n" ); document.write( "\"mu+=+M+%2B-+t%28s%5BM%5D%29\"\r
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\n" ); document.write( "\n" ); document.write( "where:\r
\n" ); document.write( "\n" ); document.write( "\"M\" = sample mean
\n" ); document.write( "\"t\" = t statistic determined by confidence level
\n" ); document.write( "\"s%5BM+%5D\"= standard error = \"sqrt%28s%5E2%2Fn%29\"\r
\n" ); document.write( "\n" ); document.write( "given\r
\n" ); document.write( "\n" ); document.write( "\"M=+13.5\"
\n" ); document.write( "\"n=15\"
\n" ); document.write( "\"s=0.77\"
\n" ); document.write( "\"c=+0.90\"\r
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\n" ); document.write( "\n" ); document.write( "A \"90\"% Confidence Interval will have the same critical values (rejection regions) as a two-tailed \"z\" test with \"alpha+=+.10\".\r
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\n" ); document.write( "\n" ); document.write( "\"zc-CI90-Table-1024x426\"\r
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\n" ); document.write( "\n" ); document.write( "so, z-score for \"90\"% confidence interval is ±\"1.6445\"\r
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\n" ); document.write( "\n" ); document.write( "\"mu+=+M+%2B-+t%28s%5BM%5D%29\"\r
\n" ); document.write( "\n" ); document.write( "\"mu+=+M+%2B-+t%28sqrt%28s%5E2%2Fn%29%29\"\r
\n" ); document.write( "\n" ); document.write( "\"mu+=13.5+%2B-+1.6445sqrt%280.77%5E2%2F15%29\"\r
\n" ); document.write( "\n" ); document.write( "\"mu+=+13.5+%2B-+0.326948217125689\"\r
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\n" ); document.write( "\n" ); document.write( "\"90\"% confidence interval is [\"13.17\", \"13.83\"]\r
\n" ); document.write( "\n" ); document.write( "You can be \"90\"% confident that the population mean (\"mu\") falls between \"13.17\" and \"13.83\".\r
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