How Many Hairs on the Human Head?

This is something I have always wondered, but never actually took the time to figure out. Today I looked this up on the internet and from what I have found, there are about 100,000 to 150,000 hairs on the human head depending on what hair color you have. Some websites that I used to find this information were http://bionumbers.hms.harvard.edu/bionumber.aspx?s=n&id=101509&ver=2
and http://mathforum.org/library/drmath/view/61887.html. 

But I also wanted to find out how to do this using math. The way that I figured out how to do this was to first find the surface area of my head.  Next I would have to measure off a fraction of my head and find out how many hairs are in that part of my head. Next I would find out how many of those sections of hair would fit within the surface area of my head. Then I would multiply that number by the number of hairs in one section to finally find out the total number of hairs

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