statistics
posted by kasey on .
The amount of snow fall falling in a certian mountain range is normally distributed with a mean of 83 inches, and a standard deviation of 16 inches. What is the probability that the mean annual snowfall during 64 randomly picked years will exceed 85.8 inches?

Use this formula to find z:
z = (x  mean)/(sd/√n)
With your data:
z = (85.8  83)/(16/√64) = ?
Once you have the zscore, look at the ztable to determine your probability.
I hope this will help get you started.