In a lottery game, one can win $10,000 with probability 0.01 and $1000 with probability 0.05. How much should one pay for a lottery ticket to make the game fair?
We calculate the expectation:
Winnings Probability Winning×probability
$10000 0.01 $100
$1000 0.05 $50
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Expectation = $150
So on the average if someone entered this same lottery free many times,
they would expect to average winning $150 per time they entered.
So for the game to be fair, one would have to expect $0, and thus one
should pay $150 per ticket.
Edwin