Some researchers needed to estimate how many catfish were in a local river, so they marked 280 catfish with tags. Later, the researchers trapped 540 catfish, of which 27 had tags. To the nearest whole number, what is the best estimate for the catfish population?
Q. Some researchers needed to estimate how many catfish were in a local river, so they marked 280 catfish with tags. Later, the researchers trapped 540 catfish, of which 27 had tags. To the nearest whole number, what is the best estimate for the catfish population?
Set up proportion: Step 1: Set up the proportion based on the capture-recapture method.Marked catfish found: 27Total catfish caught in second sample: 540Total catfish marked initially: 280Let N be the estimated catfish population.The proportion is set as:54027=N280
Solve proportion: Step 2: Solve the proportion by cross-multiplying to find N.27×N=280×540Cross multiply:27N=151200
Isolate N: Step 3: Divide both sides by 27 to isolate N.N=27151200N=5600
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