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Probability (1 Viewer)
- Thread starter kazemagic
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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
sorry i dont really understand what do you mean by general
Sy123
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Ah yes, little error on my part, my bad
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
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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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!!
