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    Was wondering if there was anywhere anyone new of with solutions to the OCR S2 textbook by Steve Dobbs and Jane Miller? Or if not, the particular question I could do with help on is question 6 in exercise 4A:
    "An unbiased dice is thrown once. Write down the probability distribution of the score X and show that Var(X) = 35/12.
    The same dice is thrown 70 times.
    (a) Find the probability that the mean score is less than 3.3.
    (b) Find the probability that the mean score exceeds 3.8."
    Thanks
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    The answers in the back are (a) 0.155 and (b) 0.0662, but I don't know how to get to them!
 
 
 
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