Question

A biologist wants to estimate the number of fish living in a lake. She caught 195 fish, tagged each one, and then released them back into the lake. After a few days, she caught 258 fish, and found that 17 of them were tagged. Use a proportion to estimate the number of fish living in this lake.

Answer 1

3120

Explanation:

so from every 258 fishes, 17 of them have tags. Population of tagged fishes is 195.

simply, ceil(258/17)×195=3120

Answer 2

Answer: The best estimation of number of fish living in this lake is 440.

Explanation:

Since we have given that

Number of fish caught that are tagged = 195

Number of fish caught by them = 258

Among them, number of tagged = 17

Number of fish that are untagged is given by

`258-17\\\\=241`

total number of fish living in this lake is given by

`195+241\\\\=436`

Hence, the best estimation of number of fish living in this lake is 440.