posted by Jay on .
Each female of a certain species of fish lays 100 eggs each fall and then dies. If only 30% of these eggs mature to become egg-producing females the next year , then how many egg-producing females will descend from a single egg-producing female 2 years after she first lays eggs ?
30% of the 100 eggs from the 1st female will mature, or 30 eggs.
Start: 1 female lays 100 eggs, and 30 mature for the next year
1 year later: 30 females lay 3000 eggs, and 900 mature for the next year
2 years later: 900 females lay 9000 eggs, and 2700 will survive