SOLUTION: A random sample of n=100 observations is selected from a population with u=30 and sigma=25. P(X>28)

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Question 1135892: A random sample of n=100 observations is selected from a population with u=30 and sigma=25.
P(X>28)
Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
If I assume the population is normal the probability is a t df=99
t=(x bar-mean)/s/sqrt(n)
>=(28-30)/25/sqrt(100)
>=-2*10/25=>-0.8
This probability is 0.7872