document.write( "Question 317453: Suppose that the percentage returns for a given year for all stocks listed on the New York Stock Exchange are approximately normally distributed with a mean of 12.4 percent and a standard deviation of 20.6 percent. Considering drawing a sample of n = 5 stocks. Find the mean and the standard deviation of the sampling distribution of X, and find an interval containing 95.44 percent of all possible sample mean returns.\r
\n" ); document.write( "\n" ); document.write( " I don't have any work to show because I have no idea where to start. I would appreciate any assistance you can give me. Thanking you in advance for your time and effort. Have a beautiful day.\r
\n" ); document.write( "\n" ); document.write( " Natasha j
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Algebra.Com's Answer #284024 by butterflyinschool(1)\"\" \"About 
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Suppose that the percentage returns for a given year for all stocks listed on the New York Stock Exchange are approximately normally distributed with a mean of 12.4 percent and a standard deviation of 20.6 percent.
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\n" ); document.write( "Considering drawing a sample of n = 5 stocks. Find the mean and the standard deviation of the sampling distribution of X,
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\n" ); document.write( "The mean of the sample means of size n=5 = 12.4%
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\n" ); document.write( "The standard deviation of the sample means of size 5 = 20.6%/sqrt(5) = 0.0921
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\n" ); document.write( "Note: To understand this read what your text says about \"The Central
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\n" ); document.write( "Find an interval containing 95.44 percent of all possible sample mean returns.
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\n" ); document.write( "Draw the picture of 95.44% centered on the mean. That puts 0.4772 to the
\n" ); document.write( "left of the middle, leaving a left-most tail of 0.0228.
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\n" ); document.write( "Find the z-value with a left tail of 0.0228
\n" ); document.write( "InvNorm(0.0228) = z = -1.999
\n" ); document.write( "Correspondingly, there is an upper bound of z = +1.999
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\n" ); document.write( "Find the corresponding x-values
\n" ); document.write( "x = zs + u
\n" ); document.write( "x = -1.999*0.0921 + 0.124 = -1.78%
\n" ); document.write( "x = 1.999*0.0921 + 0.124 = 30.81%
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