Question

Trout are bred in a tank as fish for restaurants.

Twenty trout are caught and each is tagged through the tail then released back into the tank.

A week later, thirty trout are caught and it is found that two of them have a tail tag.

Based on this evidence alone, what estimate can be made of the total number of trout in the tank?

A) 100 B) 300 c) 600 D) 1,200