Michael from Los Angeles asks, "Let's say the first man, Adam did NOT eat the forbidden fruit. Then he would have procreated with Eve in the Garden of Eden and produced a family who would have procreated with each other to produce a bigger family who would have procreated with each other to have an even bigger family and on and on. How long would take for the population of this 'family' to reach, say, 5 million persons? Keep in mind these persons not only never die, they never age past 20 years physically. There is no sickness and they are ALL fertile at age 16. There is no pain assoiciated with child birth and every child is born perfectly healthy. Let's say they are equally male and female and begin to procreate at age 16 and, to make the math simpler, each couple only has one child per year. How long would it take for their number to equal 5 million?"

Well, Michael, once in awhile I get a question that interests me enough that I don't just answer it, I do additional exploration to amuse myself. And you're in luck, because I'm sharing my additional exploration with you.

You see, today while I was on my lunch break between teaching Algebra One and Algebra Two, I created a "population explosion simulator," which allows you to enter a variety of parameters, such as initial population, death age, number of years between child births, etc.

The default parameters for the simulator are the parameters which satisfy your question.

Population Explosion Simulator!

Enjoy!