document.write( "Question 856515: While writing an article on the high cost of college education, a reporter took a random sample of the cost of new textbooks for a semester. The random variable x is the cost of one book. Her sample data can be summarized by the following. (Give your answers correct to two decimal places.)
\n" ); document.write( " n = 27, Σx = 3689.6, and Σ(x - x)2 = 9809.4 \r
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Algebra.Com's Answer #515978 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( "use 136.65 for mean and 6.15 for ME
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document.write( "n = 27, Σx = 3689.6, and Σ(x - x)2 = 9809.4 
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document.write( "mean = 3689.6/27 = 136.65
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document.write( "SD =  = 19.42
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document.write( "ME = 1.645(19.42)/sqrt(27) = 6.15
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document.write( "  136.65 - 6.15 <  < 136.65 + 6.15
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document.write( "  130.5 <  < 142.8\r
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