Answer: -0.74 cents
Using the formula:
Where:
x = value of an outcome
P(x) = probability of that outcome
For the given problem, we have 9000 tickets, out of which one will win a prize of 2300. That means that 8999 people will pay $2, with a probability of 8999/9000 losing, and the winner will get a value of $2300-$2 = $2298 with a probability of 1/9000 winning.
Expressing these into the equation:
Therefore, the expected value is -0.74 cents.