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miss
06-05-2010, 09:44 AM
Hi I have one question on probability that I am stuck on.
The question is:
Suppose we have a normal distribution with mean of 10 and standard diviation of 2. What is the probability that a value Y selected is less than 6.5?

Any help would be appreciated thanks

BGM
06-05-2010, 10:49 AM
If you are using a software, then you just need to plug in the numbers to get the answer.

If you are using a table, then you probably need to use the following fact:

X \sim N(\mu, \sigma^2) \Rightarrow \frac {X - \mu} {\sigma} \sim N(0, 1)

as the usual normal table is refering to a standard normal random variable