Question 1208186
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Tickets for a raffle cost $18. There were 757 tickets sold. One ticket will be randomly selected 
as the winner, and that person wins $1900 and also the person is given back the cost of the ticket. 
For someone who buys a ticket, what is the Expected Value?
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        The expected value of which distribution ?



<pre>
In such problems, usually two different expected values sit in and are considered for a gamer.


One expected value is the expected value of winning for a gamer.  It is 

    {{{1900/757}}} = 2.50990753 dollars.


In this specific problem, the winner pays $18 for his ticket, but then obtains 
these $18 back, so we can do not count these mutually annihilate operations.
Regarding the winner and the winning ticket, in this problem we only need to count the winning amount of $1900.



Another expected value is the expected value of the game for a gamer.  
In this problem, 756 tickets of 757 tickets lose $18 each, and one ticket of 757 tickets wins $1900.
So, the expected value of the game is 

       loosed     winning   final
       tickets    ticket    expectation

    {{{-(756*18)/757}}} + {{{1900/757}}} = -15.4663144  dollars.



Since the problem does not concretize, which of the two possible expected values is of interest,
I make two conclusions from the post. 


    - First is that the problem, as it is worded, is posed incorrectly (it is incomplete).


    - Second one is that the author does not know a subject,
      does not know how the problem should be worded,
      and is not sure to which of the two expected values his question goes.
</pre>

In formulation of a mathematical problem, everything must be clean and clear.


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In the post by @mccravyedwin, the logic of the solution and the final answer are incorrect.