document.write( "Question 970038: What is lowest passing grade of 300 students, if the lowest 10% of the students are given a failing grade. Calculate the lowest passing score with the mean of 80, and standard deviation of 10 \n" ); document.write( "
Algebra.Com's Answer #593250 by Boreal(15235)\"\" \"About 
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The lowest 10% on the normal distribution is at z=-1.28\r
\n" ); document.write( "\n" ); document.write( "-1.28= (score-mean)/sd\r
\n" ); document.write( "\n" ); document.write( "-1.28= (score-80)/10
\n" ); document.write( "multiply by 10 both sides\r
\n" ); document.write( "\n" ); document.write( "-12.8=score -80\r
\n" ); document.write( "\n" ); document.write( "add 80 to both sides\r
\n" ); document.write( "\n" ); document.write( "score=67.2
\n" ); document.write( "if no decimals, 68 would not quite include the lowest 10%, and 67 would include a little more than 10%.
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