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oceanwalk
Nov7-10, 09:39 AM
1. The problem statement:
A set of measurements of a parameter x has a normal distribution with mean of 50 and standard deviation of 1. If there are a very large number of measurements, approximately what percentage of measurements would you expect to be in the range 48 < x < 50?


Relevant equations
I have no idea


3. The attempt at a solution
Again, I have no idea.
1. The problem statement, all variables and given/known data



2. Relevant equations



3. The attempt at a solution

chaoseverlasting
Nov11-10, 12:15 AM
Normal distribution refers to the bell curve. Here's a link to check out. Go through the explanation and try to work it out. After you've given it a shot and you end up getting stuck, let us know and we'll help you out.

http://en.wikipedia.org/wiki/Normal_distribution

statdad
Nov11-10, 02:35 PM
if the measurements are normally distributed, in a large sample of them you should see the percentages follow those given in the Empirical Rule. That rule tells you the percentages to expect from \mu - k \sigma to \mu + k \sigma for the cases k = 1, 2, and 3. Use that, with a handily drawn sketch, to answer your question (I don't get that the intent is to use a probability calculation here).