Answer:
The expected value of a ticket is of -$5.
Explanation:
The expected value of the ticked is the probability of earning each prize multiplied by the prize, and subtracted by the value of the ticket.
Value of the ticket:
$10.
100 tickets are sold. They will award one first prize of $300, one second prize of $150, and one third prize of $50.
Thus, 1/100 probability of earning $300, 1/100 probability of 150 and 1/100 probability of 50. So

The expected value of a ticket is of -$5.