how many people live in the Earth?
486211
Here is the official Wolrd Population Clock\n\nhttp://www.census.gov/ipc/www/popclockworld.html
183857
My guess would be approximately 2.5 billion.  I love children!!!
14771
According to the International Data Base (IDB) maintained by the US Census Bureau, the current world population is:\n\nTotal:   6,445,820,979
353194
Well, there are fewer than 10 billion people and the average mass is less than 100kg, so the total mass of people will be less than 1 trillion kg. This is 10^12 kg. The mass of the earth is about 6*10^24 kg, so the total mass of people is less than one 6 trillionth of the mass of the earth. Not a huge effect.
771712
You ask an interesting question, actuallly.  The techniques used to answer this question keep getting refined and the equipment keeps improving, which allows scientists to make better estimates on this number.  Current estimates have it at roughly 125 billion.  Now, new technolgies may change this estimate - as knowledge improves, scientists reserve the right to change their minds.  :)
1139364
There are actually around 1.2 million described species, and current estimates say that about another 5-30 million species are left to be named.  To give you a little perspective about numbers, if you took a giant scale and put all the people on earth on one side and all the ants on the other, the ants would probably outweigh the people, and that's just ants... Again, current estimates say that insects outnumber humans 1-2 billion to 1, so that's about 12 billion billion, probably a conservative estimate at that....
499665
i guess 1 billion people
704977
5 billion seems like way too many, given that the population of the entire planet is 6 billion.\n\nI have heard the 55 million figure passed around in conversation.
856288
.World population\n\nMap of countries by population —showing the population of the People's Republic of China and India, the only two countries to have a population greater than a billion. (See List of countries by population.)\nThe world population is the total number of humans alive on the planet Earth at a given time. As of late 2006, the world population reached 6.5 billion.[1] In line with population projections, this figure continues to grow at rates that were unprecedented prior to the 20th century.
1091079
6,525,170,264 was the world population in July 2006 .\n\nMaybe they know of some space aliens watching .
71583
In rough numbers, the world has about 6 billion people\nand the US has about 300 million, so that's roughly 5%.\n\nUsing more accurate numbers from the US Census bureau:\nworld = 6,494,760,917\nUS    = 298,009,292\nwhich works out to be about 4.6%
815939
Not sure I understand your question....\nThe total mass of the earth is 6x10^24 kg.\nThe total human world population is about 6.6 x 10^9. Assuming an average weight of 50 kg, this give a total human mass of 3.3 x 10^11 kg, far smaller than the earth.  \nThe total biomass (all plants and animals together) is estimated here\nhttp://en.wikipedia.org/wiki/Biomass\nat about 2x10^15 kg, still 9 orders of magnitude smaller than the mass of the earth.
885205
Around 7 billion and growing rapidly, unevenly in the different regions of Earth. It is expected that by the half of this century that number will double.... just imagine what we`ll do with the forest and wild life and the balance on the planet, carbon emissions....
139089
According to the International Programs Center, U.S. Bureau of the Census, the total population of the World, projected to 02/13/06 at 22:14 GMT (EST+5) is\n\n6,497,535,673\n\nBelow is a cool program that counts the number of people in real time.. check it out, it also tells you the number of people on a particular day.
46613
About a 110 billion humans.
623600
6.25 billion people!!!\n\n5.05 billion lives in undeveloped countries.
171299
Africa is the world's second-largest and second most populous continent, after Asia. At about 30,370,000 km² (11,730,000 sq mi) including its adjacent islands, it covers 5.9% of the Earth's total surface area, and 20.3% of the total land area. With over 840,000,000 people (as of 2005) in 61 territories, it accounts for more than 12% of the world's human population.