An analysis of the final test scores in this class shows that the scores follow the normal distribution. The mean of the distribution is 85 and the standard deviation is 7. The professor wants to award an A student whose score is in the highest 9% which means 91% of the class will have lower grades. What is the cut-off point (or score) for those students who earn an A versus those that earn a B? In other words, what is the lowest grade an A student can earn? Hint: solve for “x”
Added by Gonzalo F.
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Given that the highest 9% of the distribution corresponds to a z-score of 1.34 (from standard normal distribution tables). Show more…
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