SOLUTION: The mean score on a history test was 74.3 and the standard deviation was 5.7. Assuming the scores are normally distributed,what fraction of scores are above 80?

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Question 476769: The mean score on a history test was 74.3 and the standard deviation was 5.7. Assuming the scores are normally distributed,what fraction of scores are above 80?
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
The mean score on a history test was 74.3 and the standard deviation was 5.7. Assuming the scores are normally distributed,what fraction of scores are above 80?
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z(80) = (80-74.3)/5.7 = 1
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P(x > 80) = P(z > 1) = normalcdf(1,100) = 0.1587
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Cheers,
Stan H.
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