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The original true mean is 31 with a standard deviation of 9. With the top 12%...

The original true mean is 31 with a standard deviation of 9. With the top 12% of grades being an A, the next 20% are Bs, the next 35% are Cs, the next 25% are Ds, and the rest (8%) should not pass. (a) Between what two scores would a student earn a B? (b) If the goal is to generate the same percentages for all grades as the original distribution, what would the new curved average and new standard deviation be if the curved range for B grades was set between scores of 80 and 90?

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