$1 and $2 bets

Supposing you were playing roulette and made even-money bets on Red.
Your starting bankroll is 40 dollars. You can’t hope to get ahead if you wager $1
each time and collect after every win.
As a smart gambler you bet bigger using your winnings, not the money you
brought to the table.
This is what would happen if you were on a winning streak and you bet-back your
winnings plus one dollar from your original stake in each consecutive round:
1. Round: Bet $1, win $1, and collect $2
2. Round: Bet $2 plus $1, win $3, and collect $6
3. Round: Bet $6 plus $1, win $7, and collect $14
4. Round: Bet $14 plus $1, win $15, and collect $30
5. Round: Bet $30 plus $1, win $31, and collect $62
6. Round: Bet $62 plus $1, win $63, and collect $126
Five- or six-round streaks are not uncommon, As long as you bet only one unit of
your own money each round, you won’t get into much trouble.