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In a large biology class, the scores of the final exam were approximately normally distributed with the mean 80.5 and standard Deviation 9.9. What proportion of final exam scores were greater than 68.3

User Kksensei
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The standardized z score is 68.3 - 80.5
-------------- = -1.263
9.9

Referring to the Standard Normal Curve tables
proportion greater than 68.3 = 1 - 0.3966 = 0.603

or 60.3%
User Shameka
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