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How to get the probability from the mean of a random variable?

  • Thread starter EGD Eric
  • Start date
  • #1
2
0

Homework Statement


From past experience, a professor knows that the test score of students taking a final examination is a random variable with mean 65.

Give an upper bound on the probability that a student's test score will exceed 75.


Homework Equations



None that I know of.

The Attempt at a Solution


I tried seeing if I could get the standard deviation, in the hopes that I could do something with that, but I don't know how to even get the variance.

I've tried looking at this problem from a bunch of different angles, writing it out, etc.. I'm seriously stuck! Any help or hints would be greatly appreciated!
 

Answers and Replies

  • #2
72
0
Is this normally distributed?
 
  • #3
2
0
I think so.
 

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