document.write( "Question 1162147: Students at Arrowhead High School took a Math test with a mean of 120 and a standard deviation of 25. Approximately, __ % of the students scored above 170. \n" ); document.write( "
Algebra.Com's Answer #785890 by Theo(13342)\"\" \"About 
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the mean is 120.
\n" ); document.write( "the standard deviation is 25.\r
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\n" ); document.write( "\n" ); document.write( "what % of the students scored above 170?\r
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\n" ); document.write( "\n" ); document.write( "use the z-score formula of z = (x-m)/s
\n" ); document.write( "formula becomes:
\n" ); document.write( "z = (170 - 120) / 25
\n" ); document.write( "solve for z to get:
\n" ); document.write( "z = 50 / 25 = 2.0
\n" ); document.write( "look up z-score in z-score table to find that the area to the left of that z-score is equal to .97725
\n" ); document.write( "since you want the percent of students who scored above that z-score, then take 1 - .97725 to get the area to the right of that z-score equal to get .02275.\r
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\n" ); document.write( "\n" ); document.write( "multiply that by 100 to get 2.275% of the students scored above 170.\r
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\n" ); document.write( "\n" ); document.write( "here's the table i used.\r
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\n" ); document.write( "\n" ); document.write( "https://www.math.arizona.edu/~rsims/ma464/standardnormaltable.pdf
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