Honestly, he was already in the team before he actually knew it, he didn't really have a choice "16/02/2011 Joined antou"
Hmm... I think coloring hats is enough. If you can color your whole character, how could you see which team the players are in ?
I can say "Irish Wristwatch" =] . For the first image, you just can't think with fractions with this kind of things (I'm not thinking of the fishes ofc ^^')., because if you put, for example, 4 pink (!) fishes and 4 black fishes in the first tank, you get 4/8=1/2 for the first tank but : 4/8 + 1/3 means 5/11 according to the logic of the picture. But 5/11 does not equal 2/5, so I think it proves it's just a bad way to use fractions, here ^^. What's happening to me... I'm using maths...