How long will it take for the entire population of China to walk past you in a single file line?

Answer 1

I was told that it would never end at the rate of the population growth, and with the number of people there. Well, one person will pass you every 1.5 seconds. There are 1.3 billion people on china. 1.3 billion times 1.5= 1,950,000,000 seconds divided by 60= 32.5 million minutes divided by 60= 540,000 hours which is about 61 years! It will take the entire population of China about 61 years to pass you!!!

But,Then all the people who were born during that 61 years have to pass. So,Given：

China's Total Population (2007) ＝1.32129 billion (official number),

China's Population Growth (2007) ＝6.81 million (to make it simple, we suppose this number doesn't change over years), and

Time Needed by Each Person to Pass You ＝1.5 seconds (taken from the text above).

Now we can calculate as follows:

People Past You Each Year ＝365×24×60×60÷1.5 ＝21024000

"Net" People Past You Each Year (deduct the annual growth) ＝21024000－6810000 ＝14214000

Total Years Needed ＝1321290000÷14214000 ≈ 93 Years

Hence,I wish you a long life! :-) Note:The math used above is a simple linear equation, whereas population expansion more closely resembles an exponential model (in essence, as there are more people there are more children, who then have even more children, so each generation is more populous). The reason you heard that it would never end due to reproduction is that the exponential model grows very big, very fast. That model is also flawed, however, and the truth lies somewhere between the two values. Humorous Note:It would be tough for them to reproduce if they were constantly walking toward you. And really, how mean would it be to send their newborn children to the back of the line?