+479 Scientists tag 100 salmons in a river. Later, they caught 50 salmons. Of these, 2 have tags. Estimate how many salmons are in the river.
tysm for any help
+129930 Just a simple proportion
2 / 100 = 50 / N cross-multiply
2N = 100 * 50
2N = 5000
N =5000/2 = 2500 salmon
Another way to see this is to note that 1/50 of the salmon are tagged
So....there are 50 times as many as we find tagged
So...if we find 50 tagged....then 50 * 50 = 2500
