Number of picks and edge

[paigow]

I've been trying to calculate something since a while and I've got no idea how to do this. Quite few math experts
here so I hope someone would be able to sort this out for me

Let's say I take 1.3 odds only. Let's say bookie comission is 5% and bookie is considered as sharp so odds reflect true probability. How many bets I need to place to make sure I've got an edge and it's not an coincidence that I make a profit? Any calculations or suggestions welcome.

 

[liveroulette]

I guess there was a mistake in question. Im gonna correct it then: we don't know if odds reflect true probability. So how many bets needs to be placed to make sure I've got edge?