To determine the number of deer in a game preserve, a forest ranger catches 343 deer, tags them, and releases them. later 128 deer are caught and its found that 73 of them are tagged. estimate how many there are in the game preserve.

First of all, one wants to ask what is the percentage of the caught deer which are tagged? This can be calculated by expressing the ratio between tagged deer and caught (the second time).



(there is no need to be so exact, but remember to calculate with as many digits you can)

Later on, by assuming that the ratio is the same, we could calculate how many are in the game preserve. This is done by making an equation, where D is the number of deer in the preserve. The equation states:



So the answer is around 600 deer.