document.write( "Question 662286: The mean score on the the exam was 63%. The Standard deviation was 12%. Find the smallest interval about the mean that contains at least 82% of the scores. \n" ); document.write( "

Algebra.Com's Answer #412083 by ewatrrr(24785) $\"\"$ $\"About$

You can put this solution on YOUR website!

 
\n" );
document.write( "Hi,
\n" );
document.write( "μ = 63% and  σ = 12%  
\n" );
document.write( "Find the smallest interval about the mean that contains at least 82% of the scores
\n" );
document.write( "(100-82)/2 = 18/2 = 9% on either side
\n" );
document.write( "z = 1.341
\n" );
document.write( " 1.341 = (x-63)/12
\n" );
document.write( " 1.341*12 + 63 = 79
\n" );
document.write( " 79-63 = 13
\n" );
document.write( " 82% of the scores will be between 50%-79%  \n" );
document.write( "

\n" );