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Pip and Bud are playing a game. Each time Pip has to flip a £$$1$$ coin. If Pip gets a head, Bud will pay him £$$1$$. If Pip gets a tail, Bud will take one of her coins. After they played $$50$$ rounds, how much would you expect Pip to gain or lose? 
Overseas Competition->Knowledge Point->Counting Modules->Statistics and Probability
Nil 