document.write( "Question 1071195: A doctor randomly selects 40 of his patients and obtains the following frequency distribution diagram regarding their serum HDL cholesterol. Use the frequency distribution diagram on the right to approximate the mean and standard deviation for serum HDL\r \n" );
document.write( "\n" );
document.write( " HDL Level Number of patients \n" );
document.write( " 30-39 6 \n" );
document.write( " 40-49 8 \n" );
document.write( " 50-59 8 \n" );
document.write( " 60-69 18\r \n" );
document.write( "\n" );
document.write( " - \n" );
document.write( "X = \r \n" );
document.write( "\n" );
document.write( "S= \n" );
document.write( " \n" );
document.write( "
![\"\"](\"/images/stars/iconNewId_16x16.gif\")
