document.write( "Question 733002: Hello, please advise, having issues with this question.\r
\n" ); document.write( "\n" ); document.write( "The scores on a national test were normally distributed with a mean of 83 and a standard deviation of 8. \r
\n" ); document.write( "\n" ); document.write( "If 400 test takers were selected at random, how many of them would you
\n" ); document.write( "expect to have a score lower than 75? (Round to the nearest person)
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Algebra.Com's Answer #852810 by ikleyn(53763) $\"\"$ $\"About$

You can put this solution on YOUR website!
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\n" ); document.write( "Hello, please advise, having issues with this question.\r
\n" ); document.write( "\n" ); document.write( "The scores on a national test were normally distributed with a mean of 83 and a standard deviation of 8. \r
\n" ); document.write( "\n" ); document.write( "If 400 test takers were selected at random, how many of them would you
\n" ); document.write( "expect to have a score lower than 75? (Round to the nearest person)
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document.write( "75 is one standard deviation below the mean:  75 = 83 - 8.\r\n" );
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document.write( "Use the empirical rule for the normal distribution:\r\n" );
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document.write( "    the area under the normal curve on the left of one standard deviation below the mean \r\n" );
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document.write( "    is  0.5 -  = 0.5 - 0.34 = 0.16.\r\n" );
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document.write( "Therefore, the number of persons with the scores below 75 is  400*0.16 = 4*16 = 64.    ANSWER\r\n" );
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\n" ); document.write( "\n" ); document.write( "Solved.\r
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