how many miles of blood vessels are in the average human body
I've seen the estimate range from 50,000 to 100,000 miles. Go to: http://www.sln.fi.edu/biosci/heart.html and click on vessels. You'll see it stated that there are over 60,000 miles (97,000 kilometers) of blood vessels in a child's body and close to 100,000 miles (161,000 kilometers) in an adult's. The circumference of the earth at the equator is 25,000 miles.