3 body collision

[GreenSabbath]

What equation should I use to represent a 3 body inelastic equation .. two ball of different masses falling together and colliding with the stationary ground.

And any hints on deriving the two body equation shown below

[whitay]

momentum before equals momentum after.

or you could calculate the centre of mass. but that would only work for a two body collision (i think).

[Doc Al]

Why don't you describe the exact problem you are trying to solve?

[GreenSabbath]

Im writing a research essay on balls of different mass falling from a fixed height onto the floor. Divided into two parts, I first vary the mass of the top ball and then for the next part I vary the mass of the bigger base ball. No Im using the general inelastic equation.. attached above and I need to go about first deriving it and then incoporating a collision with the floor. So a 3 body collision?