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    Hi guys so this question is getting on my nerves - I can't see how they get the median probability for 20? I have done all of the possible combinations and I still get 56/125? I have got (20,20,20), 3(20,20,50), 3(10,20,20), 3(10,20,50) and there's still more apparently, maybe it's an obvious one but I can't seem to get it?

    cheers

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    (Original post by iMacJack)
    Hi guys so this question is getting on my nerves - I can't see how they get the median probability for 20? I have done all of the possible combinations and I still get 56/125? I have got (20,20,20), 3(20,20,50), 3(10,20,20), 3(10,20,50) and there's still more apparently, maybe it's an obvious one but I can't seem to get it?

    cheers

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Views: 70
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    The list seems complete as regards the values of the coins, although it should be 6(10,20,50)
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    (Original post by ghostwalker)
    The list seems complete as regards the values of the coins, although it should be 6(10,20,50)
    How comes?
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    (Original post by iMacJack)
    How comes?
    Number of arrangements of 3 distinct objects = 3! = 6

    a,b,c
    a,c,b
    b,c,a
    b,a,c
    c,a,b
    c,b,a.
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    (Original post by ghostwalker)
    Number of arrangements of 3 distinct objects = 3! = 6

    a,b,c
    a,c,b
    b,c,a
    b,a,c
    c,a,b
    c,b,a.
    Awesome cheers!
 
 
 
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