6 billion people in the world. 2 die every sec, 5 born every sec. how long before original 6 billion are dead?

Question

if there are roughly 6 billion people in the world, and 5 people are born every second, and 2 people die every second, how many years will it be before the original 6 billion people are dead and replaced with a new generation of people?

Answer 1

This can be done in several ways, depending on what you need.
You can either look at the person of the original 6 billion who is going to live the longest from this point onwards (last survivor question).
You could also answer the question based on probability, when those 2 people die, what's the probability that they are a member of the original 6 billion, that'll get ugly because that equation will depend on time and other factors.
Or you can just assume that the oldest people die, therefore if two people die every second, how long will it take to get all 6 billion at that rate, well,
6 billion /2 per second, is 3 billion seconds, which is 95 years;
http://www.google.com/search?q=3+billion+seconds+in+years&ie=utf-8&oe=utf-8&aq=t&rls=org.mozilla:en-US:official&client=firefox-a

Answer 2

Of the "two die every second" is that just of the original 6 billion or of the new generation as well? Because then I can't tell. If it's just of the original generation, then it would take 3 billion seconds to kill the old generation.

Answer 3

3 billion seconds before the originals are gone. The decay rate is 2 dead per second. Just divide that number by the original amount.

Answer 4

Any answer given would have to be considered subjective due to added factors which may afterwards be applied. Such as, the governments decision to allow new deadly influenza viruses loose on the population each year, the AIDES virus, the occasional war, and the soon to occur nuclear war that will devastate 1/3rd of mankind over 1/4 of the earth, beginning in the middle east, just around the Euphrates River!!! Let's not forget the continual spread of mad cow disease that the meat producers continue to ignore, 125 different mutating S.T.D.'s, world food crops are being ruined with genetic manipulation. I think the 6b might be dead a whole lot sooner than we all might think!!! Let's all pray for better days!!!

Answer 5

The current world average life expectancy is 67 years.

So statistically, in 67 years all 6 billion people who are on the earth right now should be dead.

Answer 6

it will take to long because people are always multiplying.