What are we talking here? Some random guy with some training or someone like Vitor Belfort fighting 100 untrained people?
I would say someone at the UFC level would win all 100 fights barring some lucky punch from the untrained fighter.
Someone with just a bit of formal training would be different. If they knew what they were doing, I'd say they would win more than lose, but it really depends on how much experience they have and if they can actually apply it to a real fight.