Originally Posted by CJ Sch
Two players rolled up in same hand:
1/424 (1 player) * (remaining 7 players) 7/424 1 in 25707
I think I'm getting leveled here but I'll continue anyways...
As I stated above, it's 1/425 rather than 1/424 (unless you are trying to say 424:1 against, in which case it's just your denotation that's wrong with respect to a solo rollup.) Also, the second rollup is NOT an independent event so the math you are using is flawed.
To illustrate, I will use the probability of two rollups with only two players in the game:
The first rollup is (52/52)
The second rollup is (48/49)
The probability of each roll up is different. For one, for the first rollup the first card does not matter. For the second rollup, he can start with any card except for the case card of the first roll up. Second, there are fewer cards left in the deck.