### Statistics question

Ok so I've never taken statistics, but I'm pretty sure this is a statistics problem. My professor for my operating systems course curves test grades based on a standard deviation. If this is the template for grades:

 pt > u + 1.0 o A u < pt < u + 1.0 o B u - 1.0 o < pt < u C u - 2.0 o < pt < u - 1.0 o D u - 2.0 o < pt F

Where u is the average score, pt is my score, and o is the standard deviation. The average score was a 57, standard deviation was a 12.3, what score would I have needed to get an A?

If I read this right, wouldn't it be a 69.3?
Yes.

As a side note, this expects that 15.84% of the test-takers will get an A, and 2.27% will get an F.
Funny thing about education these days (learn for the exam, forget after), I remember doing stats in one of my math classes, and I remember all of those terms you used, but I have absolutely no idea what they really mean or what to do with them.
 Funny thing about education these days (learn for the exam, forget after)

This is unfortunately true for a lot of classes, even ones I found interesting. If it's outside my major, then I tend to not remember it. It's just knowledge that doesn't get used after the class is over.

 2.27% will get an F

How does this work? If the average is a 57%, it seems as if there would be more people who scored < 60%
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 How does this work? If the average is a 57%, it seems as if there would be more people who scored < 60%
Note that neither the curve nor the mu may reflect the actual performance of the class. It's likely that mu and sigma are precomputed based on data from previous years.
If somehow the distribution of scores for your class was uniform, then all grades will be more or less equally likely.
The numbers I quoted follow from the implicit assumption made when someone uses that curve, that scores are normally distributed; i.e. that scores closer to the median are more likely.
The F range is farther (2 sigmas minimum) from the median than the A range (1 sigma minimum), so it's less likely.
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Helios, I swear you know everything related to mathematics haha
I just happen to be taking the right classes at just the right time, I guess.
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