How Many Times Can a Human Chain of the U.S. Population Wrap Around the Earth?

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To determine how many times a human chain of the U.S. population can wrap around the Earth, one must first calculate the circumference of the Earth, which is approximately 40,000 kilometers, not the radius of 6.37 million meters. With a U.S. population of about 300 million people, if each person stands approximately one meter apart, the chain would stretch significantly. The discussion emphasizes the importance of estimating values rather than relying solely on data found online. Participants suggest using known distances, such as between major cities, to help estimate the Earth's circumference. Ultimately, the problem illustrates the need for a clear understanding of basic geometric principles.
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1. If the entire population of the United States forms a human chain by holding hands, how many times can such a chain be wrapped around the Earth's equator. Round your answer to the nearest integer.



2. There were no formulas given for this problem. I googled the length of the Earth's equator: it is 6.37 *10^6m and I know that the United States has about 300 million people



3.I tried multiplying 300 million with 6.37*10^6 and got the answer wrong. I'm completely desperate now; I don't have enough information to solve this problem
 
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The length of Earth's equator is not 6.37*10^6. That is its radius. You need to multiply this by 2pi to get the circumferance.

You might be able to space your people a little farther than 1 meter apart.
 
The point of this kind of problem isn't to google the data - it is to be able to find a way of estimating the values you need, at least to within a factor of a few.

So the circumference of the earth. The metre was originally defined as 10,000,000 the distance form the equator to the North Pole, so the eath's circumference is about 40,000Km. If you didn't know this - what's the distance between say New York and LA, howmany time zones apart are they. Since there are obviously 24 timezones around the Earth you can get the circumference.
 
vintagefreak said:
I tried multiplying 300 million with 6.37*10^6

Why did you decide multiplying was the thing to do?
 
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