Lets attack this one at a time.
For the unifrom distribution on (a,b) in your case (0,1)
For 1) mean = sd =
What do you get?
Now what will you do for ?
1. Let X be the mean of a random sample of size 12 from the uniform distribution on the interval (0, 1). Approximate P(1/2 < X < 2/3)
2. Let X be the mean of a random sample of size 36 from an exponential distribution with mean 3. Approximate P(2.5 < X < 4)
The first one I don't understand how to get the expectation and the variance.
The second one I have no idea because it's exponential.
Thanks for the help.