Question 259029
The loan officer rates applicants for credit. Ratings are normally distributed. The mean is 240 and the standard deviation is 30. If 36 applicants are randomly chosen, what is the probability that they will have a rating between 230 and 260? 
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Find the t-score of 230 and of 260:
t(230) = (230-240)/[30/sqrt(36)] = -2
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t(260) = (260-240)/[30/sqrt(36)] = 4
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P(230<=x<=260) = P(-2<= t <= 4 with df = 35) = 0.9732
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Cheers,
Stan H.