A naturalist for a fish and Game department estimated the total number of rainbow truot in a certain lake using the popular capture-mark- capture technique. He netted,marked and released 200 rainbow trout. A week later, allowing for thorough mixing, he again netted 200 trout and found 8 marked ones among them . Assuming that the proportion of marked fish in the second sample was the same as the proportion of all marked fish in the total population, estimate the number of rainbow trout in the lake.

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