Posted by nichole on .
The mean of a set of normally distributed data is 550 and the standard deviation is 35.
What percent of the data is between 515 and 585?

Math 
MathMate,
Normalize 515 and 585, namely
z(515)=(515550)/35=1
z(585)=(585550)/35=1
The percent is the difference of probabilities of onetail zvalues between 1 and +1. It should be a little less than 70%.