SOLUTION: A conservationist caught and tagged 86 trout. A person fishing caught 20 trout, 10 of which were tagged. How many fish can the conservationist expect to be in the lake?

Question 585859: A conservationist caught and tagged 86 trout. A person fishing caught 20 trout, 10 of which were tagged. How many fish can the conservationist expect to be in the lake?
Answer by KMST(5328) (Show Source): You can put this solution on YOUR website!
If half of the fish caught are tagged, the conservationist will estimate that about half of all the fish in the lake were tagged. And if he is the only one that's been tagging them, then half of the trout in the lake was 86 (before the fisherman started fishing). So there must have been about trout in the lake. If the guy who caught them does not throw them back, now there are 20 less, for an estimate of trout in the lake.
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