To let Ruth know how long her fish will live, her father tells her that well-cared fish can live 2 years longer than dogs live. On average, dogs live 4 times as long as hamsters live. And hamsters live an average of 2.5 years. How long can a fish live?
Knowing that dogs live 4 times the age of hamsters, dogs live 4 * 2.5 = <<4*2.5=10>>10 years.
If Ruth takes care of the fish, it can live 10 + 2 = <<10+2=12>>12 years.
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