A question about the odds

[frood]

Please can you try and help me understand something. This is European roulette.

A single number has a 1/37 chance of winning 36 units. Or 2.70% chance.

A double street has a 6/37 chance of winning 6 units. Or 16% chance.
Therefore if you bet a single unit on a double street then put the 6 units received back onto another double street and win again you also win 36 units.

However, the chance of winning 2 double streets in a row is (6/37)^2. Or 2.62%

So even though I'm betting the same amount of money, and winning the same amount of money, the chance of a guessing the correct number is greater than winning two double streets in a row.

This says to me that statistically, you are always better off with single bets than betting on any kind of progression. Am I right?

[/size]But this is why I'm confused. I expected on the same game, with the same amount bet and the same amount  won the odds would be the same.

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