Posted by michelle on .
mean cholesterol is 175mg/dl..standard deviation =20mg/dl assume approx normal distribution ..is varied.
what percentage has a cholesterol level above 155mg/dl?

statistics 
bobpursley,
http://davidmlane.com/hyperstat/z_table.html
see first applet. I get about 84 percent 
statistics 
blag,
Fck this problem