0
$\begingroup$

If I bet on red vs. black, I need to double the money on every loss to keep getting profit: 

1 * 2 = 2 - 1 = 1
2 * 2 = 4-3 = 1
4*2 = 8 - 7 = 1

etc. etc.

Now my question is, what formula should be considered when you bet on 2to1 when chances of wining are 1/3 (excluding 0). how should you progressive bet in this place? there is no need to double the money, correct?

  • 0
    What do you mean by "excluding zero" ? – 2017-02-09
  • 0
    Also, I presume you mean 2 to 1 *against* ? – 2017-02-09
  • 0
    let's assume there is no 0 in roullete, yes 2 to 1 – 2017-02-09

1 Answers 1

0

To attempt to win $1$ unit (the first bet, if it wins, pays $2$ units but after that, I assume you will settle for $1$), the bet after the $k$-th loss must be $$ \left(\frac32\right)^{k-1} $$