document.write( "Question 610145: a mean score on a standardized test is 50 with a standard deviation of 10. (a)What scores fall between -1 and +1 standard deviation? (b) What percent of all scores fall between -1 and +1 standard deviation? (c) What score falls at +2 standard deviations? (d)What percentage of scores falls between +1 and +2 standard deviation? \r
\n" ); document.write( "\n" ); document.write( "I have: a. 50+10=60, 50-10=40\r
\n" ); document.write( "\n" ); document.write( "b. 60%,40%
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\n" ); document.write( "d. 40%, 30%
\n" ); document.write( "What did I do wrong? \n" ); document.write( "

Algebra.Com's Answer #384170 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( " a mean score on a standardized test is 50 with a standard deviation of 10.
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document.write( "(a)What scores 'x' fall between -1 and +1 standard deviation? 40 < x <60
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document.write( "(b) What percent of all scores fall between -1 and +1 standard deviation? ~68%
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document.write( "(c) What scores falls at +2 standard deviations? 
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document.write( "(d)What percentage of scores falls between +1 and +2 standard deviation? 95.4-68.2 = 27.2%
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document.write( "For the normal distribution: 
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document.write( "one  standard deviation from the mean accounts for about % of the set 
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document.write( "two standard deviations from the mean account for about %
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document.write( "and three standard deviations from the mean account for about %.
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