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Probability (1 Viewer)

kazemagic

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O_O So the ratio of tagged to non tagged is 8 to 30? Why isnt it 8 to 22? Doesnt it mean that for every 8 tagged fish there will be 22 non-tagged fish?
Thanks bro
 
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barbernator

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the ratio of tagged to non tagged is 8:22, but the ratio of tagged to fish in general is 8:30
 

Sy123

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Note that it doesnt matter what approach we apply to the ratio:

Ratio of:

tagged : non tagged

8 : 22

Let x be the number of fish be in the tank after 50 added before 30 taken
So the ratio will be:

50 : (x-50)

Solve for x you get x=187.5
 

kazemagic

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Note that it doesnt matter what approach we apply to the ratio:

Ratio of:

tagged : non tagged

8 : 22

Let x be the number of fish be in the tank after 50 added before 30 taken
So the ratio will be:

50 : (x-50)

Solve for x you get x=187.5
Oh thanks! but for the 50 : (x-50) The question said: "Fifty tagged fish were released into a dam known to contain fish." So the question was saying that there wasnt any tagged fish in the dam b4 the fifty was added
 
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Sy123

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Oh thanks! but for the 50 : (x-50) The question said: "Fifty tagged fish were released into a dam known to contain fish." So the question was saying that there wasnt any tagged fish in the dam b4 the fifty was added
Yes but we dont care about how many fish were in the damn before 50 were added, since we are asked to estimate 'fish in the dam just prior to the sample of thirty being removed.'

Note the word prior to thirty removed, so this was when there were indeed 50 tagged fish in the damn. So our ratio stays intact
 

kazemagic

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Yes but we dont care about how many fish were in the damn before 50 were added, since we are asked to estimate 'fish in the dam just prior to the sample of thirty being removed.'

Note the word prior to thirty removed, so this was when there were indeed 50 tagged fish in the damn. So our ratio stays intact
Ohhh alrity thx!! :)
 

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