First find how much longer the second generation's tails are: 25% * 16 cm = <<25*.01*16=4>>4 cm
Then add that length to the first generation's tail length to find the second generation's tail length: 4 cm + 16 cm = <<4+16=20>>20 cm
Then find how much longer the third generation's tails are: 25% * 20 cm = <<25*.01*20=5>>5 cm
Then add that length to the second generation's tail length to find the third generation's tail length: 5 cm + 20 cm = <<5+20=25>>25 cm
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