Answer:
$82.875
Step-by-step explanation:
From the given information:
Assume F is used to denote the two cards;
If there are four aces among 52 playing cards, the chance of selecting the first ace is = 
After selecting the first ace, we have only 3 aces remaining and a total of 51 playing cards. Thus, the chance of selecting the second ace will be 
By applying product rule, we can determine the chance of selecting two aces without replacement as follows:
i.e.


The probability of getting one ace, one face is:



Since there are 4 aces, 4 nine, and 12 faces in a card deck
The probability of getting one ace, one nine, or two faces now will be:


Now, the probability of at least 20 now is:


If H represents the amount of prize of the expected winnings:
Then;



80H - 800 = 5830
80H = 5830 +800
80H = 6630
H = 6630/80
H = $82.875
The prize should be $82.875 to make a winning positive.