I am posting my question and answer. Can't seem to figure out any of these problems (the program won't accept my answers). My tutor is busy and can't help me.
Tickets for a raffle cost $\$13$. There were $739$ tickets sold. One ticket will be randomly selected as the winner, and that person wins $\$1700$ and also the person is given back the cost of the ticket. For someone who buys a ticket, what is the Expected Value (the mean of the distribution)?
If the Expected Value is negative, be sure to include the "-" sign with the answer. Express the answer rounded to two decimal places.
MY ANSWER
$-10.66$ is this right or wrong?
How I got my answer:
$$-13(738/739) + 1713(1/739)$$
Best Answer
$E[X] = \frac{1713}{739} - 13 = -\$10.68$
This is because you are always putting in \$$13$, but get back \$$1713$ once in $739$ tries.