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need help,please

GSCEstudent2020

Ragnar's Trout Sanctuary is trying to find out how many trout there are in a lake.
They catch a sample of 87 trout and tag them. They then release these trout.
The next day they catch another sample of 70 trout and find 14 of these trout had been tagged the previous day.Estimate the total number of trout in the lake.

0 trout

Original post by reena08

0 trout

I don't mean to sound rude but
HOW CAN THERE BE 0 TROUT WHEN THERE HAS ALREADY BEEN 87 TROUT CAUGHT 1 DAY AND 70 THE NEXT!?

Reply 3

ClappedKid

Original post by GSCEstudent2020

I don't mean to sound rude but
HOW CAN THERE BE 0 TROUT WHEN THERE HAS ALREADY BEEN 87 TROUT CAUGHT 1 DAY AND 70 THE NEXT!?

Because I already caught all the fish for my dinner therefore there's none left in the lake :colone:

Reply 4

GSCEstudent2020

Original post by clappedkid

because i already caught all the fish for my dinner therefore there's none left in the lake :e

screw you *****! That's not helpful stupid idiot!

Reply 5

username1732133

We can write two ratios.

Marked fish in the sample : All fish in the sample.

Marked fish in the lake : All fish in the lake.

We assume that these ratios are approximately equal.

Is that enough to get you started?

Reply 6

WHAT IN THE

17/40 fish were tagged right? so wouldn't it be 17:23? IDK just guessing :confused:

Reply 7

Lucy6487

I would have just assumed you use the formula for biology (fish in first sample which are marked and released x fish caught in second sample) / fish marked in second sample. So 87*70/14?

Reply 8

username1732133

Original post by Lucy6487

I would have just assumed you use the formula for biology (fish in first sample which are marked and released x fish caught in second sample) / fish marked in second sample. So 87*70/14?

That gives the correct result and is good as long as you remember the formula. It's even better if you can work it out without reference to a formula.