calc odds Set vs Set

[Bco1/75]

How would I calculate the odds that my opponent flopped a set if I flopped bottom Set? Ramdom assumptions (no read on player)

Thanks,
Bco

[LetYouDown]

Assuming you were playing heads up...

Say the flop is 9-5-3 and you have 3-3.

There's C(47,2) hands he can hold. 6 total combinations of 9-9 and 5-5.

6/C(47,2) = ~0.555%