document.write( "Question 333728: According to Investment Digest (\"Diversification and the Risk/Reward Relationship\", Winter 1994, 1-3), the mean of the annual return for common stocks from 1926 to 1992 was 15.4%, and the standard deviation of the annual return was 24.5%. During the same 67-year time span, the mean of the annual return for long-term government bonds was 5.5%, and the standard deviation was 6.0%. The article claims that the distributions of annual returns for both common stocks and long-term government bonds are bell-shaped and approximately symmetric. Assume that these distributions are distributed as normal random variables with the means and standard deviations given previously. \r
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document.write( "Find the probability that the return for common stocks will be greater than 9%.
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document.write( "Find the probability that the return for common stocks will be greater than 25%.
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Algebra.Com's Answer #239175 by stanbon(75887) ![]() You can put this solution on YOUR website! According to Investment Digest (\"Diversification and the Risk/Reward Relationship\", Winter 1994, 1-3), the mean of the annual return for common stocks from 1926 to 1992 was 15.4%, and the standard deviation of the annual return was 24.5%. During the same 67-year time span, the mean of the annual return for long-term government bonds was 5.5%, and the standard deviation was 6.0%. The article claims that the distributions of annual returns for both common stocks and long-term government bonds are bell-shaped and approximately symmetric. Assume that these distributions are distributed as normal random variables with the means and standard deviations given previously. \n" ); document.write( "=============================== \n" ); document.write( "Find the probability that the return for common stocks will be greater than 9%. \n" ); document.write( "z(0.09) = (0.09-0.154)/0.245 = -0.2612 \n" ); document.write( "P(x > 0.09) = P(z> -0.2612) = 0.6930 \n" ); document.write( "---------------------------------------- \n" ); document.write( "Find the probability that the return for common stocks will be greater than 25%. \n" ); document.write( "z(25) = (25-15.4)/24.5 = 0.3918 \n" ); document.write( "P(x > 25%) = P(z > 0.3918) = 0.3476 \n" ); document.write( "===================================== \n" ); document.write( "Cheers, \n" ); document.write( "Stan H. \n" ); document.write( " |