Asked by Jenna

There is a new water park in your neighbourhood. A rider is not allowed to get on the slide at the top until the previous rider has comletely exited at the bottom. It is known that the mean ride time for this type of slide is 24.5 s and the standard deviation of ride times is 6.3s.The data are normally distributed. The park operators measures the ride times of the first 30 riders.
a)what is the probability that the mean ride time is less than 22s?
Thanks
Answered by Reiny
Your question is perfectly suited for this applet

http://davidmlane.com/normal.html

Just enter your data