A frog pond has five frogs living in it. Some frogs laid eggs, and now there are three times as many tadpoles growing into more frogs as there are frogs. Two-thirds of the tadpoles will survive to maturity as frogs. The pond can only sustain eight frogs. How many frogs will have to find a new pond when the tadpoles grow up?
Please reason step by step, and put your final answer within \boxed{}.
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