Cara is a farmer who has noticed a lot of snails eating her vegetables and wants to estimate the number of snails on her land. She sets up traps and catches 38 snails. She marks the snails, releases them, and replaces the traps. Later, when she returns to the traps, she counts 170 snails, 17 of which are marked. To the nearest whole number, what is the best estimate for the snail population?
Q. Cara is a farmer who has noticed a lot of snails eating her vegetables and wants to estimate the number of snails on her land. She sets up traps and catches 38 snails. She marks the snails, releases them, and replaces the traps. Later, when she returns to the traps, she counts 170 snails, 17 of which are marked. To the nearest whole number, what is the best estimate for the snail population?
Set up proportion: Step 1: Set up the proportion based on the capture-recapture method. Cara marked and released 38 snails, then later captured 170 snails, 17 of which were marked. We set up the proportion: total snails in second capturemarked snails in second capture=total snail populationmarked snails released17017=p38
Solve for p: Step 2: Solve for p using cross multiplication.Cross multiply to find p:17×p=38×17017p=6460
Isolate p: Step 3: Divide both sides by 17 to isolate p.p=176460p=380
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