Automatic Calculations // Making Excel Count and Display progressively.

Here's the excel file with a formula that I have in it. I didn't write this formula, I have no idea how to make formulas.
satvleli.xlsx

Here's the deal. This is kind of a roulette game counter. in Bets field (upper one) is an amount that you win on a single number in this case 36, cause on roulette you win 36$ if you bet 1$ which means 35$ on top of your 1$. 36 times a bet.


in the field lost before is the amount that you have lost playing before. e.g. you were betting on some number and it didn't really show up.

in the field BET (middle one) has to be written an amount of money to be placed as a bet. When you input the amount in this middle field (BET) the third field on the right (that says win) automatically counts all the money that you have lost playing before(1st field on the left) the amount of money that you have betted now (when you won)(the middle BET field) and calculates what have you really won. (which means it gives you thing like this REAL WINNING-Lost Before-Current Bet=What's Left and gives you the amount that you've won on top of all that. That is actually what appears in this last field with a formula).


Now what I want to do is, I want to change this script in this way. I want to have a field where I can enter the amount of money that I want to win e.g. 100$ and make the script calculate and give me the amount of money that has to be placed as a bet EACH TIME I have to make a bet if I lose 299 times. So basically my maximum range of betting is 300 bets. I want to know how much do I have to bet each time to win the whole amount that I have lost before, the amount I've betted currently and 100$ on top of it.

I think this is very complicated, but let me give more explanations and clarifications if not understood.

Thank you very much for help.