Question 119515
This is a way of estimating the size of a wild population that
cannot conveniently be counted.
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Here is the proportion usually used:
Total population / number caught 
= tagged population released/tagged population caught later
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Your problem:
total deer counted: 64
tagged deer counted: 24
total deer tagged: 64
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Total population/ 64 = 64/24
Total pop = 64^2/24 = 170 2/3; rounded up is 171
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Cheers,
Stan H.