document.write( "Question 233454: The test scores of 40 students are summarized in the frequency table below. Find the standard deviation.
\n" ); document.write( "Score Students
\n" ); document.write( "50-59 12
\n" ); document.write( "60-69 8
\n" ); document.write( "70-79 10
\n" ); document.write( "80-89 5
\n" ); document.write( "90-99 5\r
\n" ); document.write( "\n" ); document.write( "Ive never done standard deviation on numbers that are ranged, so I dont even know how to set up the problem.
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Algebra.Com's Answer #172389 by stanbon(75887)\"\" \"About 
You can put this solution on YOUR website!
The test scores of 40 students are summarized in the frequency table below. Find the standard deviation.
\n" ); document.write( "Score Students
\n" ); document.write( "50-59 12
\n" ); document.write( "60-69 8
\n" ); document.write( "70-79 10
\n" ); document.write( "80-89 5
\n" ); document.write( "90-99 5
\n" ); document.write( "Ive never done standard deviation on numbers that are ranged, so I dont even know how to set up the problem.
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\n" ); document.write( "You use the class mark as the representative value for each class.
\n" ); document.write( "The class mark for the 1st class is (59+50)/2 = 109/2 = 54.4
\n" ); document.write( "And the frequency of that value is 12.
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\n" ); document.write( "Do the same for each class. Then determine the std.
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H. \n" ); document.write( "
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