Answer: $7.60
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Work Shown:
1/500 = 0.002 is the probability of winning $390
3/500 = 0.006 is the probability of winning $230
16/500 = 0.032 is the probability of winning $170
Multiply the probabilities with their respective winnings
0.002*390 = 0.78
0.006*230 = 1.38
0.032*170 = 5.44
Then add up those results
0.78+1.38+5.44 = 7.60
which is the expected value.
Side note: This game is not a fair game because mathematically a "fair game" is defined as such where the expected value is 0; ie, neither the player nor the dealer win and things break even.