this is the text of my problem
"One standard test have been used many years in a class. The test can give a max of 100 points. The sum can be considered as normal distributed. $\mu = 85, \sigma = 25$
Make a 95% confidence interval for the sum."
So i'm not sure how i should do this. I've tried to find examples around the web but it looks like there are a lot of ways to do this. I need some help so i can get myself on the right track. At this point i'm stuck