this is one of the best sites for your kind of question
http://en.wikipedia.org/wiki/List_of_countries_by_life_expectancy
enter
mean -- 28
SD ---2
click on below, enter 33
I get .99379
Times for a surgical procedure are normally distributed. Method A has a mean of 28 minutes and a standard deviation of 2 minutes for completion.
What is the probability that a surgical procedure conducted by method A takes at most 33 minutes to complete?
3 answers
Is that site the one you meant to post?
no, sorry, must have missed the "copy" before the "paste"
try this one ....
http://davidmlane.com/hyperstat/z_table.html
try this one ....
http://davidmlane.com/hyperstat/z_table.html