Answer :
ANSWER:
$-4.18
STEP-BY-STEP EXPLANATION:
The expected value would be a subtraction between the products of the probabilities of winning and losing with their respective prizes.
in case of winning where the probability is 1 among the total number of tickets sold, the prize is the value of the ticket plus $1800
But in case of losing, the 7 dollars are lost, the probabilities would be the total of the tickets minus 1 divided by the total of tickets
Given:
P (winning) = 1/643
P (losing) = 642/643
Therefore:
[tex]\begin{gathered} E=\frac{1}{643}\cdot(7+1800)-7\cdot\frac{642}{643} \\ E=2.81-\: 6.99 \\ E=-4.18 \end{gathered}[/tex]Therefore, the expected value is $-4.18