Question 1186121
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Tutor @ikleyn solves the problem using the formal definition of expected value; that is probably what the student was expected to do.<br>
For simple problems like this, the expected value can be determined less formally with less work.<br>
The total cost of the 713 tickets sold was 713($12) = $8556.<br>
The total payout was $1800+$12 = $1812 (the person who won the prize also got back the cost of his ticket).<br>
The net loss to the players was $8556-1812 = $6744.<br>
The average loss for the 713 tickets sold was $6744/713 = $9.4586.... or about $9.46<br>
ANSWER: The expected value for each ticket sold was -$9.46<br>