one question

well, I did post this in another forum, but I just realized I probably should have posted it here. I've just been having trouble with this one problem that I cannot seem to get.

A hot dog stand has a daily demand for hot dogs on a weekend follows a normal distribution with a mean of 400 and a standard deviation of 50.

Find the probability that the sample mean demand for a random sample of 4 weekend days will be less than 300.

I tried the central limit theorem, but it didn't work, and there wasn't enough info to do the finite population correction. Can anyone help?
I think you just need to find the z-score for x-bar = 300 and sigma = 50 and look it up on the SND table.

you're trying to make this hard again....