document.write( "Question 1136419: In a recent year, the ACT scores for high school students with an A or B grade point average were normally distributed with a mean of 24.2 and a standard deviation of 4.2. A student with an A or B average who took the ACT during this time is selected.\r
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Algebra.Com's Answer #754464 by Theo(13342)\"\" \"About 
You can put this solution on YOUR website!
mean is 24.2 and standard deviation is 4.2.\r
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\n" ); document.write( "\n" ); document.write( "you can use the following calculator to answer this question.\r
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\n" ); document.write( "\n" ); document.write( "http://davidmlane.com/hyperstat/z_table.html\r
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\n" ); document.write( "\n" ); document.write( "your solution will be:\r
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\n" ); document.write( "\n" ); document.write( "probability that a score is less than 21 is equal to .2231.\r
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\n" ); document.write( "\n" ); document.write( "the results are shown below:\r
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\n" ); document.write( "\n" ); document.write( "probability that a score is greater than 33 is equal to .0181.\r
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\n" ); document.write( "\n" ); document.write( "the results are shown below:\r
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\n" ); document.write( "\n" ); document.write( "if you wanted to solve this using z-scores, you would do the following:\r
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\n" ); document.write( "\n" ); document.write( "the formula for z-score is z = (x-m)/s\r
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\n" ); document.write( "\n" ); document.write( "z is the z-score.
\n" ); document.write( "x is the raw score.
\n" ); document.write( "m is the mean.
\n" ); document.write( "s is the standard deviation.\r
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\n" ); document.write( "\n" ); document.write( "m is 24.2
\n" ); document.write( "s is 4.2\r
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\n" ); document.write( "\n" ); document.write( "when x = 21, the z-score is (21 - 24.2) / 4.2 = -.7619048\r
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\n" ); document.write( "\n" ); document.write( "when x = 33, the z-score is (33 - 24.2) / 4.2 = 2.095238095.\r
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\n" ); document.write( "\n" ); document.write( "you would use the same calculator, only you would set the mean to 0 and the standard deviation to 1.\r
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\n" ); document.write( "\n" ); document.write( "you would get the same answers as before, only this time you are suing the z-score rather than the raw score.\r
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\n" ); document.write( "\n" ); document.write( "here's the results.\r
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\n" ); document.write( "\n" ); document.write( "for less than -.761905.\r
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\n" ); document.write( "\n" ); document.write( "for greater than 2.095238.\r
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