Hi Hurkyl
Possible scenario
We choose the 3rd Dozen and the 1st Column
So, to begin with ,we choose the numbers
1,,4,7,10,
13,16,19,22
25,26 27 28, 29 30 31 32,33,34,35,36
a total of 20 numbers an advantage of 20/37
We also consider all the Red / Odd and Black / Even numbers
These are ;
1,2,3,4,5,6,7,8,9,10
19,20,21,22,23,24,25,26,27,28 - again 20 numbers an advantage
of 20 / 37
The chances of both winning on the same spin are 20 / 37 multiplied by 20 / 37 which is 400 / 1369.
Choosing only those numbers which they have in common we now have 1,4,7,10,19,22,25,26,27,28 a total of 10 numbers
Each bet costs 10 units and for each win we receive 36 units
So over an average 1369 spins we spend 13690 units and receive 400 times 36 which is 14400 a surplus of 710 units
So we can use maths to win at roulette unless my maths is wrong which I am asking people to show.
BUT this can only be theoretical as each spin of the wheel gives a random number so no one can claim, with certainty ,that we MUST lose or win at roulette, Where uncertainty exists certainty can be claimed by clairvoyants but not by mathematicians.