[jay_shark]

Ok so you're assuming you have the same roi before the rake back .

(x-24)/24=(y-27)/27
solve for y and you get y=(27/24)x

Profit for first game is (x-24) + 0.54
Profit for second game is (27/24)x - 27

Now we wish to know when (x-24)+0.54>(27/24)x-27
(27/24)x-x<27+0.54-24
x(3/24)<3.54
x<28.32

This means that if your roi is the same before the rakeback in both games , then it is more profitable to play in the first game as long as x<28.32 . Or equivalent , if your roi before the rakeback is less than 18% .